Well, top lane is all about simultaneously trading and farming at the same time. There are two ways you can push; either a) you kill all of the melee minions, which will cause the enemy minions to have more damage but less overall health, or b) you kill all of the caster minions, which means that the enemy lane has more than half of the health but less than half of the damage of a wave. What this means is that if you choose option A, your lane will push because caster minions are squishy. They will die quickly, and not deal a lot of damage. If you choose option B, your lane will stall. This is good if you are trying to quickly push your lane. It will take time for your minions to kill the enemy melee minions, long enough for the next wave to reach you. By doing this, your lane will slowly push. Your melee minions will die, but your caster minions will not die on their own. This kind of slow pushing is great for making sure your opponent loses CS. Now, when you do this is up to you. You probably already knew a lot of this, but it is good food for thought when thinking about how to control your lane.
When you're in the top lane, you almost always want the enemy laner to overextend early on. Your jungler will start on the bottom, and he will reach topside at about level three. At this time, you want your enemy laner to be as close to your tower as possible so your jungler can gank easier whilst also denying the enemy jungler any access to a gank. To do this, simply do not auto attack your lane. Let your enemy laner push the wave. You should still last hit, but anytime you are not last hitting, you should be harassing them. As Nidalee, you will most likely succeed easily in harassing them as you are ranged.
This is just some things I've come up with off the top of my head. I try to keep most of these things in mind when I'm playing top lane, but the one thing you want to remember is that top lane is, for the most part, a solo lane. You will not receive a lot of jungler attention, because his attention is needed towards the other side of the map for dragon. Usually that first gank is all you're going to receive. Keep in mind that the enemy jungler is also going to be looking to snowball their top laner early on.
I do not play many of your champions (aside from Garen / Nasus), so this may seem very vague champion wise. I hope this helps.