Been playing with some friends of my brother on a weekly basis recently, and they asked me the same thing. Told them some observations.
Chip with something other than a PW/SW.
Quit taking soooo many practice swings. 1 max, 2 on "feel" shots
Quit lining up putts from both directions.
Play more than you practice.
The best piece of advice though that got me over the hump. Act like you care. Tuck in your shirt. Play in clean shoes. Assign a place in your bag...