At any rate i would take Flash, but you can choose between Flash-exhaust ( exhaust is really usefull because so you can land ur spears easierly) flash-ignite or Flash-teleport

I advise you to farm and poke spears until lvl 6, if youre lvl 6 you can beginn to roam with your tiger form. Before teamfights you have to poke with your spear, i advise you to poke the adc / apc low/down if possible. In teamfights you Need to remove you from th enemis if they Focus you (with tiger form). if they dont Focus you onlyl stay in the Background and spamm your heal and your spears. If you see the enemis have low life you can catch them with tiger form. but i wouldn´t advise you to go in a Teamfight with ur tigerform, so you are only instand dead

It´s very easy to troll your opponents with nidalee, 1st get tigerform 2nd go by bushes, because your passive makes you faster 3rd from the time to time throw some spears and drop your enemie lower, ,lower, lower and dead

Pros:
-Long range
-very mobile
- you can help easily your teammates (roaming, healing)
-high dmg on a single target
Cons:
-no cc
-no area-dmg