Summarize:

Draw a cross line right at the middle of the rectangle. Simply add a nose with an elongated oval. Bart's irises are simple dots. Simpsons family don't have facial hairs. Imagine where you want Bart's chest to be placed.
Start the outline sketch with a rectangle. Outline sketch the face. Draw a circle for one of the eyes. Add another circle for the other eyeball. Continue with the actual line of the nose. Add the irises. Draw one curve line as part of the eyebrow. Add the actual line for the forehead. Draw a sketch upward curve line as guide to the spiky head. Draw the actual line of the back of the head. Add the nine spikes on the head. Draw the actual line for the upper lip. Add the lower lip and the chin. Draw the ear. Erase the line that was supposed to be blocked by the ear. Add a downward curve for the neckline. Draw a circle sketch outline. Add a bigger circle for the guideline of the tummy and hips. Sketch the outline of the body. Draw two curved lines to show the center of the body. Add the outline sketches for the sleeves. Add Bart's arm and hand outline sketch. Start the actual lines with the shirt. Draw the actual lines for the sleeves, arm and hand. Draw the actual lines for the shorts. Add the legs with for side curved lines. Add the actual lines of the sneakers. Erase the outline sketches. Color the draft.