Just start with the basics. Draw all the time and draw what you see; work on still lifes and master copies. For your figurative stuff, pick up some anatomy books and do studies until you feel comfortable drawing the human form. :)
draw, draw, draw. every free moment that you have just pick up a pen and paper and draw something. it'll take you about a thousand drawings to produce a good one, so you just have to get those out of the way first. books i've studied from are "Rapid Viz" by Kurt Hanks and Larry Belliston "Constructive Anatomy" by George B.…