well for starters take alook at some of the pics others have done for you, there you can look to see how they draw.

Try some doodles dont have to be compleated skeactches graduarly build up on what you know.

last tip this is one people have always mentioned to me, get a How to draw book too, preferably ones that show you how to draw manga or marvle characters, that show how to make anatomy, if anything thats the best tip anyone can give you.