How can I turn my man on, and where is the spots that drive a man crazy?

If he's open in bed I would suggest you try stripping him down and blindfolding him(or not). This will make him focus exclusively on his senses. Do a mix of all of the above, touching, kissing, french kissing, feeling, licking, blowing your warm breath in his ear, talking dirty to him :) It's the anticipation that makes it so great. You should have no problem finding his special spots if you don't know already. Start at his ears and work down. We're not all the same, but I would guess his ears, neck, chest, center back, his sides(starting below the armpit and going to the butt) and all around the pubic area(inner/upper thigh, waist, balls) focusing last on the appendage.
Good Luck and have fun!

neck is always for a guy and kissing him all over hands on is always good too

this may kinda sound nasty but I know from personal experiences:

*my man likes it when (when you go "down" on him) lick the spot between his "goodies" and his anus. he'll really like that.

*my boyfriend also likes it when I put my breasts on his back while licking his ears and biting em.

once you get to now your man, you'll know what he'll like. but that always works for me.
hope it wasn't too explicit ;-(