You’ll want a set of good gloves when you’re molding and/or using the heat gun. The main attributes you’re looking for is for the gloves to fit you well, be as thin as possible, and at least the finger/thumb pads and entire palm is made out of suede, leather or some other material that will not melt at between 200 and 400 degrees F.
Full fingered leather sporting or driving gloves can work. As will some of the leather/Nomex tactical/shooting gloves. The best, most durable gloves we’ve found are Mechanix “Impact Pro” work gloves. They give excellent heat protection while maintaining fine dexterity. We’re hoping to add them to the store, but in the mean time you can find them at most Lowes stores. They are not cheap, but they last a long time and the leather usually wears out before the stitching.