Well, as I don't like reading big things I won't write a big one either. Nidalee is a high mobility, high risk, assassination, underestimated champion. Nidalee can really surprise her enemies when she has the Mark on the target, which you get through either a spear or a trap. So... let's get started:

Laning Phase: If the enemy is melee, perfect. Whenever he goes for a minion Auto Attack him to hell, without losing minions of course, and if you can, hit him with a spear, jump in as cougar ( W ) Use your takedown ( Q ) your Swipe ( E ) and jump out. If he dealt damage to you, no problem. You have your heal, you have some AP, you have a ring to provide you with Mana, you are set. Keep doing this until you either are fed, outfarmed him or simply destroying him.

From Laning Phase, to Split Pushing and roaming Phase: As a Nidalee top, and with Distortion boots, you can be a pain to the enemy team. Call it off to your team, explain them what you are doing and ask them to pressure mid. You will need at least 2 or 3 people on you top to catch you, meaning mid or bot will be exposed. Call this to your team and stay top. You have your teleport, in critical situations just TP there. Enemy team is on drake? Push top. Baron? Help your team but if you can't contest it, push top.

End game: You are strong, really mobile and no one can catch you without blowing summoners and even with them it's hard. You are really annoying TP'ing here and there destroying turrets keeping pressure.

It's a simple guide I think. But remmember: Call this off to your team otherwise it will be a major disaster. Good luck playing tha kitty, this was MeGonnaCatchYa, out.