Electronrider
Sharpshooter
I like to hold the front of my dominate hand with my off hand while shooting a handgun. My father swears by holding the underneath side of his shooting hand.
any suggestions?
That is an age difference. Your father is using the "cup and saucer" grip that was widely used in the past. The modern "wrap both hads around the grip" is popular now. One provides a more stable platform for shooting, while the other helps make follow up shots a lot faster.