It really depends if your going out with him or not...
If you are: You would have already made out by this point so when your making out with a guy maybe stop to kiss his neck then grab his hands and put them on you body..
Seducing means something sexual to most people. Being subtle but a little playful (less than aggressive), consider a date where you wear a short skirt and no panties (or take them off, if you do this, you should shave your pubic hair). Allow him to "accidentally" see up your skirt, or brush against him with a hand in suggestive ways (his rear, crotch), Wear a top that will let only him see your breasts when you lean forward, for instance.