Exercises for a Bigger Butt

The butt contains a three-part muscle group consisting of the gluteus maximus, gluteus medius and gluteus minimus. In your quest to enlarge your posterior side, you need to target this muscle group with weight training exercises. You can use free weights, machines and body weight to achieve your goal.
Squats
Squats are performed with a barbell inside a squat rack. Step under the bar and place it across your shoulders behind your neck. After grabbing the bar with a wide grip, lift it off the support pins, step back a few steps and place your feet shoulder-width apart. Keeping your back straight and core tight, lower yourself down by bending your knees. Once your thighs parallel the floor, stand up and repeat for 10 to 12 reps.
Lunges
Lunges can be done with a set of dumbbells. Hold the weights at your sides as you step forward with your right foot. Once your foot touches the floor, lower yourself down by bending your knees. When your right thigh parallels the floor and your left knee is an inch above the floor, come back up and step forward with your left leg. Continue to lunge in an alternating fashion until you've done 10 to 12 reps with each leg.
Stiff Leg Deadlifts
Stiff leg deadlifts are done with a barbell. Stand with your feet shoulder-width apart and hold the bar in front of your thighs with an overhand, shoulder-width grip. Slowly bend at the hips and lower the bar toward the floor. Once you feel a strong contraction in your butt, stand back up and repeat for 10 to 12 reps.
Ball Butt Raises
Ball butt raises are performed with an exercise ball. Lie on your back with your heels propped up on the ball and your arms at your sides. In a steady motion, press into the ball, lift your hips in the air and squeeze your glutes forcefully. Slowly lower and repeat for 10 to 12 reps. When doing these, maintain a slight bend in your knees.
Cable Kickbacks
Cable kickbacks are done on one side of a cable machine with an ankle cuff. Attach the cuff to a low setting and stand facing the weight stack. After fastening the cuff to your lower left leg (right above your ankle), lift your leg off the floor and push it straight behind you in an arcing motion as high as possible. Slowly lower it down and repeat. After you have done 10 to 12 reps, switch sides. When doing kickbacks, keep your working leg as straight as possible and do not let your foot touch the ground during the lowering portion.