Hiya this is my first build/guide so don't be too harsh. Well this probably won't work for everybody but it is currently working for me.
PLEASE TRY BEFORE DOWN VOTING!!! XD

The runes i use are for Magic Penetration and Ability Power. I am using these to add to Morgana's strengths rather than covering her weaknesses.

The masteries i use are in the form of 21-0-9. this is because using this guide the main goal is to take out your opponents as fast as possible with devastating outcomes for any who come your way.

I choose to max out Dark Binding first, followed by Black Shield and then Tormented Soil whilst picking up Soul Shackles whenever I can.
i choose to max out Dark Binding first as with the AP Morgana has the effects of it even early game gives a good stun and a decent ammount of damage to your opponent and its a great escape method if ghost is on cooldown.

I choose Ghost and Ignite.

The reason for Ghost is because Morgana isn't very fast so its nice to have another escape/chasing method to make up for it.

The reason for Ignite is with having Dark Binding early on you can stun your opponent and take a chunk of health away while finishing him/her off with Ignite as the stun runs out. WOOHOO FIRST BLOOD!! XD

Early game is important! People often focus on Morgana early game to stop her from getting good items later game.
The main thing to remember is that if laning with a partner stay back and go in for a kill when you see the oppertunity but don't take too many risks as that could stop your ultimate mid game.
BUT, when solo in middle all you want to do is harass your opponent and wait for the right chance to try get your fist kill when you are around Lv 5-7, any earlier could cause a death but any later may give them a chance to gank you as you start to move in.
In early game you want to get upto at least your Majai's Soulstealer and hopefully your Sorcer's Shoes.

Mid game is always fun. As your opponents haven't got mega defences yet its the perfect time to charge you Mejai's Soulstealer. This is the time for ganking. By now you should have maxed out your Dark Binding and be ready to run around the map picking your prey.
your items by now should be all the way upto Rabadon's Deathcap or working on it. (Remember you have your mastery to gain extra gold XD)
Don't forget to use the ultimate combo for Morgana:
Tormented Soil > Dark Binding > Soul Shackles
Your opponent will be stuck in the Tormented Soil and will be dealt MEGA damage by your Dark Binding as you move to get yet another stun with your Soul Shackles(if they don't die first) XD

Now here's the important bit. In late game you should have all or almost all your items and although quite squishy you will be unstoppable with your AP. By now you will be honing the map and taking down everybody with your combos. Remember that although underestimated Dark Binding is your Golden Ticket to kills with this guide USE IT OFTEN!! XD

As the team fights have really become full 5 VS 5 you are crucial but not just as a support. Go in for an early start with Tormented Soil and your Dark Binding but save your Soul Shackles for later. Don't forget you have one more skill. Dark Shield!! Very useful during the team fights especially if you use it on the allies with low defence to armour not only saving their life but winning the team fight while you are there. But don't forget that although you are spamming your Dark Shield onto your team also take down your opponents. Pick one and tease them forcing them to come after you then use your Ultimate Combo as I discussed earlier. Mega kills here!!!

If you get a chance at Lv 12 its easy to take on both the Golem and Lizard withing a couple minutes and returning to your lane with full Mana and Health!!!
Keep Jungling throughout the game where/when you see fit but don't leave your lane for too long and remember to get them if you know a team fight is on its way!

Throughout the game you will have MEGA AP causing major troubles for your opponents and making life as Morgana EASY. This build does take practice though so don't expect to be amazing right from the start but do try it a few times to get used to it before you give up as it is an amazing way to play and alot of fun whilst playing.

My latest scores have been:
- 21-2-9
- 41-8-2
- 10-4-27
- 30-15-29
Although i had 15 deaths in the bottom one it was an amazing game and we had alot of kill stealers playing with us :(

SO EVERYBODY, GOOD LUCK AND HAVE FUN.
Don't forget to "BRING THE PAIN"!! I hope you enjoyed my guide and enjoyed using it XD