i no its one tricky slut to get the hang of, ill give you a few pointers
1.grind your herb really good
2.put the flame pretty close but not touching, dont keep it stationary,swirl it a bit
3.when u start to see vapour take the lighter away and inhale kinda slow so you dont get weed flying everywhere
4.give the bulb a shake to mix the weed up
5.keep doin that until the weed is brown, if the weed is black your heating it too much