FARM GANK FARM GANK! Go up and down the river starting at lvl 8 or 9. Place some wards in the river to help your team.

There are 2 ways of ganking.
Ambush (better for AD) : Wait in the bush for your enemy place traps at least 2 of them just to be sure that your enemy will step on em. Initiate the fight with E while in Cougar form then W and Q and so on. Execute your enemy with Q Cougar or Human form its the same does ALOT of damage.
Charge : Try to predict you enemies escape route and counter him. Initiate with a Q human form and charge with cougar form then W E Q sometimes thats all you need to do to kill the ememy. :D
If the emey survives you allways have Q that has enormous range and even better damage.
Harrasing : Use your Q max range isnt nesessary cus its all abt positioning. Throw your Q mid range and run the opsite way of the spear. It normaly does around 20% to 60% of enemies max HP so dnt be ashamed to use it as ur advantage.

AP : Pros
Long range nuke <3
nuke :P
Her Q is like a kinder surprise you dont know whas gonna hit you :D
One of the best harraser
Her heal is quite good aka its a life saver
Traps rule. If you plant em around them map youll most likely get a kill or 2 when some1s escapeing hes panicing and aint gonna see the trap and die when he steps on it :D
If youre jungling traps are a life saver plant em on entrances in the jungle
AP : Cons
Youre gonna be focused nearly every fight
Shes mana hungry the entire game
Her cougar Q isnt that good
Early game ganking is quite hard
Jungling with AP Nida sux

AD : Pros
Pretty much a better nuker than Veigar or Le Blanc
Better executor than Darius
Shes like an AD carry does around the same damage in the same time
Pounce is great for close combat or for escapeing
Her E heals and adds 60% AS which is rly handy for AD champs and you ofc
She can be a nice jungler
Trinity Force stacks with her Q which is makeing ur enemies react like WOW OMG WTF WAS THAT DAMAGE
Theres more im just lazy
AD : Cons
You just need a CC for AD in this case RCS
Shes squishy
Champs with higher HP are allways better than her in early game even if they are noobs
Shes mostly AP

Talk with your team before you pick which build youre going to use. PLay agressive with AD and defensive with AP. FARM GANK FARM GANK!
Please vote and comment. Feel free to give me your opinion on everything add or remove something correct me abt something if im wrong. Ive been playing LoL for quite some time now and I started makeing guides few days ago cus i have plenty of expirince and I wanna share it with all of you guys.