You could always pocket the deck (with your card in question forced to the top or bottom) as a part of a transition to the next leg of the trick. Prime example:
As explained by Wayne, when performing distortion, as soon as you do the reveal that your card changed into theirs and they go to look at their card that they've been holding, pocket the deck and only remove the double. Then if they say "No way, lemme see the deck," take the deck back out of your pocket sans the top or bottom (depending on where you put it) card. I've been working on doing this with every card trick that involves doubles or gaffs only because it's one of the more natural looking ditches without having to go into palming or spontanious combustion... When you're done with your cards, you put them in your pocket. It's a logical progression and as stated before, and your pocket serves as a natural cover.
hope this helped
Dave