Session 1
Hip extension strength
Two weekly sessions that train the glutes from every angle: hip extension, single-leg squats and abduction.

The gluteus maximus extends the hip (moving the leg back) and the gluteus medius abducts it (moving it out to the side). A good routine combines heavy hip-extension work, single-leg work and some abduction.
Do each session once a week with at least 48 hours between them. Tap an exercise to see its technique.
Hip extension strength
Volume and single-leg
Twice a week is the most efficient for most people. If glutes are your priority and you recover well, you can add a lighter third session.
It is not required. Squats train the glutes, but hip thrusts, Romanian deadlifts and Bulgarian split squats work them as well or better.
Yes: replace your leg days with these sessions and add 1-2 quad exercises (leg press or leg extension) if you want to keep thigh work.