This is not a "make or break" decision. So don't agonize over it!
Do you want to gel? If so, covering your soap with something thick (like a towel or a box) can trap warmth in and encourage gel. If you don't want to get, I would recommend not covering, although not covering will not guarantee no gel.
Do you have a cat? I do recommend covering the soap or put it someplace a cat can't reach it, if you have a cat. Also, if you have a lot of pets (we have 9) there is a certain amount of free-floating hair. So I keep my soap covered in the mold, and when it's sliced it goes in boxes covered by cheese cloth.