Cut open two large paper bags and tape them together until you have a size that's a little longer and a little wider than yourself. Or you can use a section of a kraft paper roll.
Lie on the paper and have a partner trace around your outline.
Cut out the body shape.
Find pictures in magazines that show things that you like. Cut them out and paste them to your body outline. These could be anything from pictures of animals, to computer games, cars or musical groups.
Draw your face, shoes, etc. using pencil crayons or crayons. You might also wish to glue pieces of fabric onto your collage.