You can DHV in sets by letting another guy wear it and then looking at him funny and saying, "Nah...It looks better on me." Then you grab it off his head, don't wait for him to hand it back and you put it on with some style and then I like to run my finger and thumb around the brim a bit and say, "There.

Much better." And nod when they laugh as if they affirmed it, because that's what it is. Note the wink is at your target or any other decently attractive girls (it just doesn't work on the ugly girls for some reason, the hot girls get turned off by it I figure).
On a girl, you can do the same thing and wink at her, or you can tell her that it looks better on you, but that she can wear it for now, but its special to you, so to take good care of it. Like L.A. said its a great lock on and she won't go far.