Most of you guys think that Nidalee is just throwing spears around the map. But she is not!
Her w is a nice skill in early game.
1. She is able to get some bush vision, maybe to counter a blitz, for example.
2. The trap saves the lane of strong jungle ganks or an oracle.
3. U can use nice advanced tactics, like clearing up the blue and steal it with q.
But her heal is very nice too, because she gives some sustain and makes attack speed carries like vayne, teemo, kog maw and caitlyn very strong, because of the strong buff.
But not just the ad carry gets stronger. The passive of the Puma-e is an attack speed buff for nida as well, so that she can be played as hybrid or ad too.
But let's not forget her q.
It is the strongest poke in the game, with a very high range, and in her puma, it bursts too if u play her ad.

I use magic penatration marks, because she has got 4 magic damage skills, but just 2 stack with ap.
The rest is standard ap carry.

I use this skill order, to find a good solution to help the ad carry and poke the enemy ad carry down.
Her trap is skilled at level 1, to place some before 2:00, but it is just finished in the late game.

I use flash as a very nice and fast possibility to flash in the bush, turn in puma and get away.
Exhaust is a standard support spell, because it can turn early fights around.

I start the game with a Meki Pendant and a Sight Ward, to be able to stay on the lane and safe the lane.
After this I buy Boots of Spped and the Tear of Godness, to spam my skills.
To end the early game up, I buy Sorecerer Shoes and if I get some spear kills the Needlesly Large Rod .
Because of her big q damage, I am able to poke the ad carry hard, with a full range q he can lose half hp.
In mid game, I finish the Deathcap and buy Sheen, because of my 7 skills.
If our ap carry is not very strong, i buy the Lich Bane, but a Trinity Force is another good possibility.
Now we'll keep on with a Frozen heart if the enemies got much attack speed, if not Archangels Staff, because I got some mana with sheen and the tear.
The last item could be an Hourglass, if u are fed and focused, or a Warmogs, if your team is not tanky as well.

Pros:
- Huge Burst
- high Movement
- Vision
- Sustain
- Att. Speed Buff

Cons:
- Not tanky
- No CC
- not much help for the adc

In the early game u have to play nidalee as a suport. Just start using your spear if u got the tear, to not go out of mana. Stay in the bush to get the movement speed buff and help your carry as good as possible.
Try to safe him with some traps, because they are almost invisible.

Now you should have got your tear and maybe got 1 or 2 kills, so that you have nic damage.
Try to use safe spears on the enemies so that they cant fight with full hp.
Just turn into puma and attack, if they are low life to get more damage with the q.
If u killed 1, try to search for a bush and play safe.
Remember that your spears just get the op damage, if you throw them from max range. Try to use them if the target got somen cc for free dmg.

In the late game Nidalee gets a bit useless. Try to poke with your q so hard, that 1 carry is not able to fight, heal the teammate who needs the attackspeed and try to steal buffs with your spears.
It is important that you stay defensive with nida and wait for the perfect moment to jump in and burst the target down. If you do everything right, u can burst the ad or ap carry down alone.

To sum this guide up, nidalee is a very funny champ. She gets more and more useless in the late game, but if you can hit some nice max range spears and do not forget your support role, nidalee can get more usefull than soraka or someone else, because of her nice poke and burst damage.
I got the experience, that i had to practice her for a few games, but now she is one of my favourite champs, just because she has so much funny things to do, like jumping over the wall, throwing a spear, jumping back and bursting the target down.
Remember that Nidalee is able to jump over very much walls, which does not help very much, but it is very funny and makes her faster :).