Heat a pot of water on the stove until it starts to boil. Remove the water from the heat and allow it to cool for about 5 minutes.
Dip the gloves in the hot water until they are fully submerged. Take the gloves out of the water and lay them flat on a solid surface.
Plug the hair dryer in and go over the gloves with it on the hottest setting. Continue until the gloves are dry.
Try the gloves on to see if they are now the right size. Once they fit properly, use mink oil or leather conditioner to soften the leather, since the hot water can leave the gloves somewhat stiff.