I'm writing this for all my friends who are struggling to climb rank.
I will try to keep this guide simple and onto-the-point. (Some of the guides here are so long!!)
Therefore, I recommend all to read this word-by-word instead of skipping through.

Many people consider Morgana mid as a not-so-good mid ap champ, but it's because its play-style is a little different from other typical ap mid champions.
But, it's actually a very good mid champ and I will show you guys why in this guide.

Pros:

Strong laner that doesn't fall apart in late game
Has good CC skills
Good pushing skill
No complex mechanics
Can initiate 5v5 fight
Not ugly

Cons:

Poor jungler-gank followup
Less damage output compared to other typical mid ap champs
Skills are easily dodge-able by enemy.
Not very attractive

I call this the Basic-Ap-rune-set.

Many people just use this set for all types of mid AP champs because of lack of ip and rune page.

But if you have enough ip and rune pages, then you can make 2 rune pages and use them to gain a little more advantage in the lane phase.

Simply take out the armor runes against any ap champ opponent and take out the magic resistance runes against any ad champ opponent, and replace them with hp runes.

But I recommend playing with this "basic" rune set only, for the consistency. Also, Faker senpai likes to use these "basic" rune sets and masteries, instead of playing around with the runes and masteries. Quote, "I don't really care much about runes and masteries."

This is one of the basic 21/9/0 AP masteries.

If you are playing an assassin ap champ, give a point to double-edge-sword,
and if you are playing a high utility ap champ, you go 21/0/9 build.
But, I won't talk about these in detail here.

Go for as much AP damage as possible.

Morgana may seem like it does alot of damage output with its high q damage, but it actually lacks damage compared to other ap mid champions because q is a single-target skill and e is not an offensive skill.

Since Morgana has an awesome shield skill and since Zhonya's Hourglass is a must-have-item, you need to focus on having much ap as possible to compensate for the damage shortage.


Always start with Doran's Ring + 2 hp potions.

If you are against AD champ, skip Morellonomicon and go straight to Zhonya's Hourglass.

If you are against AP champ and you are doing horrible, go for Abyssal Scepter as your first item.

Rest are the same. Go for as much ap dmg as possible.

Give 3 W's, then max in order of r-q-w-e.

This skill sequence may seem weird but this is how most Mid Morgana player levels their skill.

Leveling W's in the laning phase is very important to push the lane faster than your opponent. (I will talk about this in detail later.)

But, it's also important to max Q as soon as possible to have longer cc duration and higher burst damage.

Hence, this build came out.

Standard:

Flash is a must and Ignite covers the damage shortage in killing the opponent in lane.
Also, since Q is a single-target skill, there are many times that you have to go 1v1 even during 5v5 fights, and Ignite makes that possible.

Other considerations:

I saw one mid Morgana player using Teleport. It may work well against champs like Twisted Fate or if your top lane is not carrying Teleport.
But I don't recommend this because you will most likely pushing the lane and your opponent won't be able to gank other lanes. Also, without Ignite, you won't have enough damage to kill the opponent even if you lane your q, which also leads to less pressure in lane.


May work well against AD champs like Yasuo and Zed. Also covers for Morgana's poor Jungler-gank followups. But you will most likely go Zhonya's Hourglass first and that will be enough for defensive measures. Therefore, I prefer going Ignite over Exhaust even against ADs but it's arguable.


Defensive spells are no good with Morgana because Morgana already has a very good shield skill.

PUSH

Push the lane. Push the lane with everything you got.

Level w first in level 1 and as soon as the creeps get to the lane, place your w so that it damages all 6 creeps, all melee and range creeps.
And! this is the most important part.
Do not miss any last hits.

At W level 1, W skill doesn't do much damage.
At W level 2, W will make all range creeps hp low enough to kill with 1 auto attack.
At W level 3, W skill will kill all range creeps.
Hence, level W up to 3 first then max Q.

Don't randomly throw W. Throw it once per 1 creep wave.
If you have enough mp maybe throw it twice to push faster.
But if your mp is short, don't use it at all and your mp will fill fast with Doran's ring.



Why push?

Pro of pushing is, if you can push faster than your opponent, you can attack the opponent while the opponent is still clearing creeps and if your opponent attack you, then the creeps will attack the opponent with you.
Hence, pushing the lane will give you huge advantage in the lane.

After the pushing your lane, attack the heck out of the opponent with basic attack.
If the opponent tries to fight back, land your Q, it will be easier to land Q.



Why Morgana is a good pushing champ?

Unlike other weak AP champs with no escape, Morgana has a good shield skill that can prevent it from getting cc'd.

Before level 4, ward one side of the river and farm by leaning towards that warded side of river.
If enemy jungler comes from the warded side, you go back.
If enemy jungler comes from the not-warded side, you can run to the warded river.

Unless you are against something like Leblac mid and Lee Sin jungler, you are not going to die from pushing.
And even if you do go against something like Leblac and Lee Sin, you can ward defensively by warding both sides of river, and continue pushing.

If you don't have wards, then control your lane by pushing just enough to keep the creep wave in the center of the lane.
Don't pull all the way, it will be even more dangerous to pull.

Junglers usually don't gank too much before level 4, unless you are against something like Elise, Shaco, Xin, etc.

Even if you mess up once before level 4, you burn a flash and probably won't die.
But keep in mind that jungler will come back if you burn a flash.
If no flash, then play safe until level 4.

After level 4, you just have to be careful when your q and e is on cooldown.



When to use Q and E

E:

You must save E for CCs.
Since your passive lets you heal with every spell damage you do, you can take some damage and heal by pushing the lane with w.

So unless your MP is full or your HP is very low, you should save your E until your opponent uses its CC skill or enemy jungler comes to your lane.


Q:

Consider your Q as similar to Blitzcrank's Q.
If you miss, you become very vulnerable to your opponent.
So how do you use it?

One way to use your Q is to not use it.
If you don't use it, enemy will be very pressured because opponent doesn't know when the heck you are going to throw that Q.
Keep pressuring enemy, act like your going to throw your Q by approaching the enemy.
But don't throw it until you can get close to your enemy.
You also save your MP by not throwing your Q so you can use your W more frequently.

Once you get a chance to approach your enemy, throw your Q but do it very smoothly.
Meaning, throw your Q when your enemy least expect it.
Throw it while moving around, throw it while your chatting(jerk), throw it as soon as the enemy creeps die, etc.
And also, try not to be too careful in aiming q. Watch how pros aim their skill shots.
They throw it very freely. If you aim too much, your skill shot will miss that perfect time to land and your aim will be actually less accurate.

Each time you land your Q you gain significant amount of advantage.

Roaming
Morgana is not the best ganking champ because Q is hard to land, unless your top or bot lane can CC first to let you chain CC.
However, Morgana is a good followup or counter-gank champ.

Followup is following enemy's gank.
If your opponent goes to other lane, simply follow the opponent.
Most likely junglers will follow as well and it will be 3v3 or 4v4.
More enemies mean easier to land Q.

For counter-ganking,
When your lane is pushed, try to predict where enemy jungle would be.
Sometimes you can predict that enemy jungler will gank a certain lane.
Be there before and land your Q when enemy comes near.



5v5s
Tell your team to wait for your Q to land.
It's the best way to start the fight for sure.

Try to land your Q from where enemies can't see you.
Use wards so that you have vision advantage.
As soon as you have advantage in vision, your Q will be much easier to lane.
If your team is losing the vision fight and if enemy team doesn't have a good initiator, just randomly use your Q from where both you and your enemy can't see each other.

(Random->Predict: To be "good" at champs like Blitz and Morg, you should be capable of making game-changing skill shot.

Try to predict when you don't have a vision. Predict where enemy champs would be standing. Enemies may be relaxing @ bush because they know you don't have a ward there,

or if you catch an enemy with a ward vision, running to somewhere, even when the enemy gets out of the vision, try to measure where the enemy would be and throw your Q.

Unless you have blue buff, you can't just randomly throw your Q. Even when you are playing a champ other than Morg, you should always try your very best to land your skill shot, even when it seems like it's not as important to land it. These small things makes difference in climbing rank.)

Or try to approach a little then throw your Q.
But when you approach the enemy team, you shouldn't trust your shield too much. Have enough distance so that you don't get caught. And you shouldn't randomly waste your Q and e if enemy has a good initiator, like Ashe.

Don't use E on yourself.
Use it on your team who really needs it. Like bruisers such as Irelia, Warwick, Jax, etc
Or if your ADC is caught by enemy CC'er.
You will most likely use your R as soon as the fight breaks out and you will most likely end up using Zhonya's Hourglass so you don't need to use E on yourself.

Do not rely on your W to last hit in the laning phase and ward aggressively more towards enemy jungle.

When enemy jungle shows up, farming jungle, steal its jungle mob or Q+W to kill or make enemy jungler go back to fountain to heal.

You don't always need to ward both side of river to survive; therefore, you can place your wards more aggressively towards enemy jungle.

If your jungler gives you blue, you can also farm jungle by yourself after pushing your lane.

One of the reason why I started playing Morgana is because my low elo jungler friend likes to go Sated build and farm jungle all day.

He doesn't gank and he doesn't even follow enemy jungle.
But, he is not the only jungle nowadays that farms all day.

Sometimes even in high elo your jungler may not pay attention to mid lane.
Some of the possible reasons can be because top or bot is losing or because top or bot has better kill potential.

Morgana is best for these kinds of situations.

The way Morgana carries the game is by pushing the lane and making enemy jungler to come to your lane, instead of top or bot.

Morgana mid is very strong against ganks because you can simply walk away with E skill and if you are in trouble, you can simply throw a Q and even if it doesn't land, the enemy has to run around it and it will buy you enough time to run to tower.

Your jungler will be able to focus more on farming or ganking other lanes.

I only use all my skills on smart cast when I play champions like Lee Sin and Katarina. For skills like Morgana's Black shield, Nidalee's heal or Kayle's Ulti, I don't have it as smart cast but I have it on self-cast smart cast. When I use shield or heal on my teammate, I use it as non-smart cast but when I use it onto myself, I use the self-cast.

Smart cast definitely has advantage over non-smart cast when you are playing on champions like Lee sin, Katarina, Ahri, Leblac, etc., but for Morgana, it may be better to not use smart cast even if you are more used to using smart cast. It will help you aim a little better and that's the most important thing you must be able to do on Morgana.

I sometimes see higher ranked players play Morgana. In overall, they are obviously better than me even on Morgana, but most of the time I see that I'm better in laning phase because they are too scared to approach and land Q.

If you can't land Q in laning phase, you will obviously lose unless the opponent just farms, which only happens in low ranks.

Morgana is okay against most champions but there are some annoying champs.

is definitely very annoying to go against because of its wind-wall and very good mobility in lane.
But I also play mid, which is a very good counter so I don't have this problem.
Don't try to act too greedy until level 6.
At level 6, you can win 1v1 by using your ulti first then Q with E to block tornado.

is a huge problem if you somehow get behind. You won't have the damage to even threat if he gets ahead. won't lose in lane but it's also hard to win against in lane. But in 5v5s can do much more than so can be the most annoying champ to go against.

is not really a counter but champions like , strong ap carry that can box magic fight and win, is not easy to win against.

if you play a mirror match, mirror will be a never ending farming game.