Look at what you have now and what the routine is supposed to look like and the style of it, Do you want grace, impossibility, cleanliness, gimmicked? Then work from there. Don't just put any coin vanish in there. It will break the action and won't look right. If you are doing this super hip flashy visual routine, you don't want to be doing something with a covered vanish, you probably want something that is visual and compliments the routine.