We will begin by practicing with some full body characters. The best thing is to first draw a skeleton for our character. I draw the head first. It will serve as scale for the rest of the body.
Form the head, I add its neck and spinal chord; the axis of the body. I have drawn it, in this case, in a curve to make my character lean on one leg and resting the other. We rarely see a person standing on both legs rigidly, unless they are in the "attention" position of military personnel.
Notice the lines that join both shoulders and hips. You can't raise one without lowering its other side. The same thing happens with the hips. Being connected to limbs, this will also happen to our knees and elbows. In other words: draw each part of the body in relation to the rest.