Practice is always #1 in these cases, however there are some tricks I usually tell people when they first learn how to drive 5speed to keep from rolling/stalling.
Trick 1: The throttle blip. Before taking off (letting off clutch) just blip the gas slightly so that you don't start from idle. This way you already build up some momentum and the car will be harder to stall. (By blipping I mean if you idle at 700RPM blip to about 1200RPM not much at all)
Trick 2: The brake trick. (usually works best when combined with Trick 1) Before letting off the brake start letting off the clutch SLOWLY as soon as you start feeling it catch get off the brake and get on the throttle. It worked wonders when I taught my gf to drive her 6 speed 350Z.
Trick 3: The e-brake. this is pretty much a variation of 2 only that you use the ebrake the hold the car in place. The only advantage over 2 is that you don't have to tool around with all three pedals at the same time and you can just concentrate on the clutch/throttle action.
I wish I could be more specific but unfortunately these sound better in real person with a demonstration.
Good Luck.