Nid is a great let's say nuke champion,when i play Nid i am almost always in the brush,and nuke enemy champions,i go cougar if there is no enemy's and then i farm minions,at team fight's when it's 4v5 or 5v5 i am always cougar but if the number reduces to 2-1/5 i go human.

One important thing about my LoL playing,i actually always at level's 11-13 go run around the map and kill til level 16.That is my tactic,i rarely play mid players.The best thing about Nid is that she can flee in and out of fights by using Cougar form and brush.Nid is a extreme good chaser,best one in game,cous of cougar,brushes,long range spear,and cougar *pounce*.No one can escape.That is why i love Nid.

Ill tel you guys a secret about Nid,when you play her NEVER i mean NEVER don't tower dive IT IS THE WORST THING YOU CAN DO WITH NIDA,cous she has got some great range options,and she has low armor,that is why i buy Zhonya's Hourglass.Till you buy that item DO NOT TOWER DIVE. That would be all.I have told you every tip i know.I gave my best,cya :D