A drill I learned from my college golf days is probably my favorite drill for short putts especially pressured short putts. It’s called beat the pro. So you set up 4 tee’s in a circle starting off at 4ft. The pro is an imaginary pro so if you miss 1 putt that’s 2 points for the imaginary pro and zero for yourself. If you make the putt that’s 1 point for yourself and zero for the imaginary pro. The first one to 21 points wins the game. Once you beat the imaginary pro from 4ft you take a step back and play the game from 5ft, and so on and so forth. This can help practice pressure situations especially when the imaginary pro has close to 21 points as well as yourself!