Start Bushwhack. Put them in every bush you see. Also, whenever they try to engage, kite them into one of them, preferably they should follow you into a bush. Then counter-attack. At this point they've probably blown their abilities and your autoattacks *will* finish them off compared to their autoattacks. Mainly because of 20% defenses shred, haha. If past level 1, then your E will make you attack quickly and have sustain enough to kill them anyways.

Try not to level her spear too much; it's not going to do much damage regardless. It does scare people into getting out of position in order to dodge, though!

Once you hit level six, you're still going to spend most of your time in human form. Once again, kite them into a bushwhacked bush. Hit Alt+E (self-cast), then go into cougar form. At this point, it's pretty much "mash buttons win". Try to stagger your cooldowns, though; they'll proc Sheen better that way. If you've already got Iceborn Gauntlet, it makes chasing even easier, too.

Late game, your goal is to... be a typical bruiser and jump in and kill things, particularly carries. You probably will die if they focus you regardless, but if they don't, you'll live, because no one can chase a Nidalee and catch up to her.

You should ward as much as possible; you're really quick, so getting places to ward them is no problem. This means you'll be in your Cougar form. Unless you have blue for some reason, don't go into human form to bushwhack places you won't be fighting at. You may get caught with your cougar form on cooldown.

As a note: Pounce doesn't go towards your cursor. It goes in the direction Nidalee is facing, which is... dumb. This ruins escapes a lot. Just remember if you're going to jump over a wall that Nidalee has to face where you wanna go, not just your cursor!

Sunfire Cape: Your autoattack range is tiny and Pounce synergizes well with it. In fact, the entire cougar kit does. Nidalee's normal kit doesn't really synergize with it, but by the time you have a Sunfire Cape, you won't be trading in human form anyways.

Iceborn Gauntlet: Q is an autoattack-based ability. I think Iceborn Gauntlet's proc interacts with its up-to-300%-damage part. Regardless, you have low cooldowns, pounce lets you get right on top of someone to autoattack, Q procs Iceborn Gauntlet, it makes you do AoE damage on ALL of your cougar form abilities, and it slows. So, you know, it's impossible to escape Nidalee's grasp.

Black Cleaver: Standard AD item. Even if you're not an AD caster, it does shred armor and gives decent survivability, on top of CDR. If you'd prefer Last Whisper since it doesn't need multiple attacks, that's a good idea, too.

Hextech Gunblade: AP for your W/E in cougar form. You can spellvamp off that stuff, too (it's a lot more than you'd think). It also gives plenty of AD and some lifesteal, which you kind of need to survive teamfights. Also, additional slows (this time from a range) to make escaping Nidalee even more impossible.

Runic Bulwark: If your tank gets this, you don't necessarily need to get it. However, getting this gives you a great deal of defensive stats. Also, the passive can go to the tank (you will both be in the fray constantly). Given your tank getting this item, Guardian Angel and Maw of Malmortius are both good alternatives.

I don't know what to say here. Just... try her out for yourself, okay? Doing well in lane early is very easy if you're very skilled. If you're not, it'll be difficult, but you do have an advantage due to range most of the time.

P.S.: If you spend all your time chucking spears, when are you ever going to get to rip someone apart with tooth and claw? Abandon all sense of society and remember the primitive.