Glute bridge.

Glute bridge

 1) Lie face up on the floor, with your knees bent and feet flat on the ground. Keep your arms at your side with your palms down.

2) Lift your hips off the ground until your knees, hips and shoulders form a straight line. Squeeze those glutes hard and keep your abs drawn in so you don’t overextend your back during the exercise.

3) Hold your bridged position for a couple of seconds before easing back down.

Note :- Make sure you’re not pushing from your heels – the power comes from the hips and nowhere else. Aim for two sets of ten bridges, two to three times a week, either as part of a wider Body weight Workout  or on their own, if all you really care about is your derriere.