Dime/Washer exercise. Get a person to place a dime or washer at tip of barrel,
practice trigger squeeze (dry fire, of course).
Use good ole US Army Training Acronym- BRAS
B reathe
R elax
A im
S queeze
I tought BRM (Basic Rifle Marksmanship) and everything an Infantryman would learn
or Airforce SP/LE Trainees at Ft. Dix for 4 years at a Joint Service School

Oz