What masturbation action can use a teenage boy

Try laying naked on your back on your bed, grab your penis and stroke the foreskin up and down over the top (head) of your penis. Just keep stroking, you can try speeding up and slowing down to make it feel better. You should find your penis will get hard and the pleasure build until you orgasm. (being 13 you may or may not cum but you should get a very pleasurable sensation)