No, you do not need a gloss surface. Though dry transfers require a different approach when applying. Once you rub the transfer onto a model, this is no second chance to reposition it, so care should be taken to line up the transfer exactly where you want it before rubbing it onto the model. If you are not familiar with dry transfers, or are a little uneasy applying them, a simple solution is to rub the dry transfer to a regular blank decal sheet, apply a dullcote, then proceed as normal with a decal.