I glue a small piece of rubber or felt to the back of the trigger guard. Works identical to wearing a thick glove. For me I shoot a Ruger XR3 or SBH grip framed revolver best with my hand pushed as high up as possible under the grip frame. But that is also the most painful way to shoot heavy loads as it places your knuckle right against the trigger guard. The felt or rubber makes a huge difference. You can also use a small piece of auto or household weatherstripping as some of these already have adhesive on them. Just cut to size and stick on.