It's basically just getting comfortable with the car, as everyone else suggested learning in a parking lot is a great place to start. It helps to know how it works.. there's two ways your car can be in neutral, if the clutch is in or if you haven't put it in gear. If the car is in gear while it's not moving it will stall. All you have to do is get it moving before you fully let off the clutch. A rough guide...
1. Find the clutch point (about an inch above the floor in most cars, but not all). Know where this is. You don't want to guess every time. Practice pushing in the clutch to this point so that you know what your foot feels like when it's there.
2. Release the clutch at a reasonable pace. Don't granny it, but don't pop it. The key word is natural. As you let it off, press on the gas. For a smooth takeoff it should be proportionate - that is, press in the gas at the same speed you're letting off the clutch.
3. To keep from stalling at stops, just dip the clutch in a little and pop the shifter out of gear. You don't want to hold in your clutch at every stop or you'll ruin it, but if you come to a stop while the car is in gear and the clutch is not in, it will stall, as I said in the first part.
It will take about a week pf regular before you feel comfortable with it, and a while after that before you fully get rid of stalls and shifting errors. It's all worth it man, driving stick is so much fun and so much better than shitty autos.
Another tip for downshifting (PRACTICE THIS ONCE YOU GET COMFORTABLE, it's part of what makes driving standard so fun) is when you press in the clutch, pump the gas as you're downshifting. The reason the car jumps when you downshift is because it has to raise the RPMs to match your new gear to the speed you're going. You'll notice if you pump the gas while the clutch is in the RPMs will spike, so once you get good you can match the RPMs ahead of time (or at least get it close) and it will make every one smooth as hell.