The two things to consider are fit, already mentioned, (and hardest to gauge) and thickness of the material. For scale modeling, thinner gloves are better.

Most come in small, medium, large, and extra large. Once you figure out your size (the tightest fit you can still get on your hands fairly easily) I use and recommend these. Don't get powdered gloves. They are messy, and many people become sensitized to the powder. Just make sure your hands are absolutely dry when putting them on.