nah dont bother about making a hand mould. much more trouble than its worth.

just put a first thin layer of silicone over all the joint areas, to form the shape, dry it, should only take about 15 mins in front of a blow heater or with a hair dryer, then take it off your hand and the shape should hold. then add more protection where you want it.

good silicone will hold to old silicone also, for running repairs, which is the big advantage of a silicone glove, so you can always add more later, unlike latex gloves. (plus silicone is a little slicker on the tiles)