and, i didn't add this but I cannot stress this enough, SHAPES! learn to add shapes into your rough sketches! got hands? use a short coffin for the palm and squares for the fingers! (the rest doesn't work for stick figure bodies but...) USE OVALS AND SQUARES FOR THE CHEST & TORSO!! Use more ovals for the legs and arms! SHAPES HELP YOU GET A GOOD BASE!!
the reason why you do the sketch in bitmap and convert it to vector is because it'll stay together like a png so you can delete it once you're done.