Champion Overview:
Nidalee is an EXTREMLY moblile champion that can be built in 2 diverse ways: A. AP Nidalee or B.) Tanky AD Nidalee. The first of which does well in poke comps, but is weaker in more direct fights and thus takes more of a support role to the team. The latter of the 2 jumps right into the heat of the fight being very tanky and hard to kill. Both builds are completly viable but they serve 2 different purposes to the team. Nidalee in top lane has all of the needs from the shop a top laner could need free wards and hp heals (In toned down spell versions). Nidalee is capable of fighting a great moajority of top laners in the game and coming out ahead. At 6 Nidalee gets a whole new set of skills and becomes a different champion, the mastering of both forms is the key to mastering Nidalee.
NOTE:You must play 10 hour nyan cat while playing Nidalee no exceptions.

Skills Overview:

Passive: Prowl- Moving through brush increases Nidalee's movement speed by 15% for 2 seconds.

A very strong passive for top lane, this allows you to have the mobility to outmaneuver most other top laners in the game. When running away or chasing always try and run through brush if possible.

Q: Javelin Toss / Takedown- Human: Nidalee tosses her javelin, dealing 55 / 95 / 140 / 185 / 230 (+65% of ability power) magic damage on impact (deals up to 250% damage the further away the target is). Cougar: Nidalee's next attack deals additional damage based on how low her opponent's life is. Cooldown 6 seconds. Cost 50/60/70/80/90 mana. Range 1500

Your core damage move on both AP and AD Nidalee, In different ways though. As AP Nidalee it will be your human version that will be your main damage, while on AD Nidalee it will be the cougar component. The spear is INSANE damage as AP Nidalee and can realistically 1/2 hp a squishy target. On AD Nidalee the bite will do surprisingly high amounts of damage and will catch alot of players off guard.
Note: A way to increase spear damage is to throw the spear and run back which will increase the distance between you and your target, as AD Nidalee remember the Q resets your auto attk timer so that you can auto then Q instantly for some good damage.

W: Bushwhack / Pounce- Human: Nidalee lays a trap that deals 80 / 125 / 170 / 215 / 260 (+40% of ability power) damage over 2 seconds, reveals the target, and reduces their armor and magic resistance by 20 / 25 / 30 / 35 / 40% for 12 seconds. Traps last for 4 minutes. Cougar: Nidalee lunges forward, dealing damage to surrounding enemies. Pounce is not affected by cooldown reduction. Cooldown 18seconds. Cost 60 / 75 / 90 / 105 / 120mana .Range 900

I do not have works to speak about how well I love this skill it is freaking amazing Both components for AD and AP Nidalee and makes her what she is. In human form you can provide mini wards for yourself that last LONGER than real wards AND reduce armor/MR. In cougar this skill is YOU, it is what makes you so godly uncatchable. These traps also reveal stealth units like a jungle twitch eve etc...
Note: If the enemy who got hit by your trap is standing on a ward they layed you will get sight of the ward.

E: Primal Surge / Swipe- Human: Nidalee heals an ally champion for 50/85/120/155/190 (+70% of ability power) and grants them a 20 / 30 / 40 / 50 / 60% attack speed for 7 seconds. Cougar: Nidelee claws at enemies in front of her. Cooldown 10 seconds. Cost 60/80/100/120/140 mana. Range 600

In human mode this is your sustain, both nidalees like this. AP nidalee does massive heal and the buff is nice for tower pushing and to give to allies. AD nidalee likes it for the attack speed and lane sustain.

R: Aspect Of The Cougar- Passive: Each additional rank increases the effectiveness of Nidalee's cougar abilities. Nidalee transforms into a vicious cougar, gaining 20 movement speed, 10/20/30 armor and magic resistance and a new set of abilities. Cooldown 4 seconds

The gate beween the 2 Nidalees. This skill allows you to transform into a whole new different just as fun character.
NOTE: IF you are chasing an enemy in cougar who is about to get away with little hp morph into a human and auto him. If you have a sheen the morph will proc it for the damage.

Combos/Skillorder:

Skill Order:
Max E>Q>W

Combo:
starting in human Q-E-R-Q-W-E-W-R-Q-W-R-W-E-Q

Yea something like that.

Matchups:
All of the logic for the easys is the same, they cant survive your hit and run warfare.

Easy:
Olaf (Sustain makes his true damage result in only hurting himself), Trundle (troll got no gap closers), Riven (You both live off trading, you trade harder, back off if she trys to full commit.) Garen (Play human used range-Profit), Singed (auto him, you wont be in poison.) and Nasus (You can zone him hard)

Hard:

Yorick(sustains harder, pokes harder he has a slow and a speed up to keep on you), Renekton (No mana he will eventually out sustain you), Akali (Burst very hard at 6 and can kill you easily), Nautilus (Shields a s sustain and wins out) and Lee Sin (Plays just like you if he maxes shield first).

Playing AS/VS:

AS:
-At level one lay traps everywhere on the map to give your team enhanced vision.
-Lay a trap at the buff your jungler is starting at and then go your lane you will not miss a single CS.
-Force trades and heal them off you will come out on top.
-Trap the lane brush to completely prevent lane ganks

VS:
-Gank Nidalee early past 6 shes almost ungankable
-Avoid stepping on her traps or she will use the pen and destroy you.
-Do not let nidalee trade with you unless you have some way to sustain her damage back.

Big Item Choices:

AD Nidalee

Wriggle's Lantern - Sustain, damage, armor, and keeps your lane warded what more could you ask for in an item?

Ninja Tabi / Mercury's Treads - good to out run the enemy, there is power in speed (Kiting, escaping, chaseing)
((OPTIONAL Doran's Blade - Helps with last hits, gives some damage, survivability, and Life steal.))

Trinity Force - Nidalee can make use of every statpoint here especially in cat mode.
What part of the trinity force do I build first?
Good Question. This is all situational You build Phage if you want survivability health and chasing power, Zeal if you want movespeed for escapeing, and sheen if you want to be able to burst down enemies faster and can spare the survivability of the phage.

Warmog's Armor - Tanky item Nid CSes very well so u can get this item this late and still fill it up.

Atma's Impaler - By this point you are a VERY tanky cat that will do massive damage at this point the game will be nearing conclusion.

Banshee's Veil - Strong Defensive item for MR and it can block 1 CC/ skill the hp will go for the atmas so in all this works out well for you.

Aegis of the Legion - gives you team a nice boost while your around which you should be tanky enough to be

AP Nidalee

Sorcerer's Shoes - They WILL buy MR for your spears so you will need the pen.

Rod of Ages - Gives you mana to hum spears and heal all lane and be tanky a pretty good all around item.

Rabadon's Deathcap - More AP more spearkills.

Lich Bane - All you AP is converted to damage and with your spammy cat nature you'll proc it alot.

Morello's Evil Tome -More spears ( AP nids trademark).

Void Staff - more pen, screw the tanks.

Gametypes:

SoloQ:
Nidalee will stomp this. You can destroy most lane opponents you will get in SoloQ. You can split push towers down all day, No one can stop you due to your insane mobility. You can complete carry games by pulling enemies away from fighting your allies to come stop you. If you are ahead you can just completely destroy them.

Ranked 5s:
Nidalee is strong here as she can be run in set comps (Poke comps/Bruiser comps) and you can tell your team that you will not need as many ganks and other things to help them win the game. Also be sure to have a microphone and turn on.. NYAN NYAN NYAN NYAN NYAN NYAN NYAN NYAN NYAN NYAN NYAN NYAN NYAN NYAN NYAN NYAN NYAN NYAN NYAN NYAN NYAN NYAN NYAN NYAN NYAN.

Conclusion:
NYAN NYAN NYAN NYAN NYAN NYAN NYAN NYAN. Nidalee is a ver strong champion capable of winning lanes, being very fun, and being a general annoyance to the enemy team all at once :D. She is one of my favorite champions and I hope you all enjoy her too.

I Have a Nidalee GUIDE out, it is kinda old and my playstyle has changed a little since then but its still kinda accurate. http://www.mobafire.com/league-of-legends/build/meow-im-a-cat-163991

SERIES UPDATE:
I plan on releasing these every day/other day until I get all of the top lane picks in the league ( about 50-60 of them) if there are any requests leave in the comments below and ill work on them. I want to make this series for others to better understand the champions of top lane. Once I am done (Or once I have a few top facts out) I will release some Facts about top lane mechanics, eventually I will probably put everything into one generic top lane guide, however until I do that I will continue to watch and update my blogs as needed. Tips and tricks I missed under my Top Facts would be helpful if you put anything I don't have in the comments I will be sure to add it. I will be forming a guide called The complete guide to Top lane or something in that nature. The intention of this series is not as a "Build guide" or a "play guide", these are more like facts you should know about the champion. These are to inspire people to think of new champion possibilities they might not have thought of or to help a new player with the champion. I do not list runes masteries or a set build ( I give a kind of recommended items) in here due to the fact I want people to think of that for themselves and try new things. This series is an attempt for the LOL community to try new things and have fun in a fun game. Thank you for reading and have a nice day:P