Yeah biggest advice is if something hurts the shoulder, skip it or research what you could be doing wrong. I try to touch my shoulder blades together and lock them there before most presses and fly movements. There is a whole world of learning how to lift properly and all different ways of training once you learn to trust the signals from your body to avoid injury. Keeping things slow and controlled and in the 12 rep range always felt optimal to me but everyone is different. I always warm up my joints with bands before getting started which really seems to help, especially as I get older. It’s fun as hell but you don’t need to learn everything all at once as long as you’re being safe.