This is a nice simply exercise you can do at home. All you need is a swiss ball or alternatively the floor will do.
Hip extension (or bridge) is an ideal / simple exercise for the toning of your posterior. The idea is to sit on a stability ball, roll out to lay flat with both feet firmly on the floor so you are a bridge with the ball, knees bent at 90 degrees, chest to the sky. Keeping tension in the core through your belly button and glutes (butt) slowly lower your hips to the floor – the ball does not move – pause then raise hips back up squeezing glutes and pause again, all for a count of 3 up and 3 down.
Incorporate this into a morning or evening routine. Start with 10 reps and work up to 30. It really is a simply exercise with lots of benefits.
When you are ready you can progress to ankle over knee hip extension or leg extension.