One kind of cool study to do is a cloth study. If you drape a sheet over a chair and draw the wrinkles it will help you to make the pants of your character become a lot more realistic. It is basically practicing to draw shadows on clothing.
Level 17 Gladiator: Spartacus' Dimachaeri
Thanked 4,259 Times in 2,074 Posts
I think the first thing about character designing is getting a good foundation down. You can find basic figure drawing stuff about everywhere, but I think for you, let's get something very basic down first. Proportion of your character to the paper you're working on. Learn to draw a proportionate stick figure so that the full character fits on that paper. This will cut the really bad habit of artists that have characters that get cut off at the knees/thighs.
Don't worry about details right now, start doing sketches of figures in sketch forms and making sure they fit on that paper.