To get the curves you want, prepare to do some lifting. When you want to add more bulk to your thighs and butt, you'll need to focus on exercises that build muscle -- which typically means doing weight-bearing or resistance exercises. Bulk up your thighs and butt by spending a little time using machine and free weights.
The weight machines at your gym or community center include a number of devices that will work out your butt and thighs. While different gyms may have different equipment, most will have a leg press or "sled" machine to help you work your butt, hips and thighs. Your gym will also probably have a leg-extension machine that focuses on the quads and a hamstring curl machine that focuses on the hamstrings and glutes. To build a lot of muscle in your quads and glutes, focus on lifting a higher amount of weight and doing fewer repetitions on these machines.
A barbell and its accompanying weight plates can also be a good addition to your arsenal when you're looking to build your butt and thighs. Three basic exercises that will help with this are the squat, deadlift and lunge. Start by lifting only the bar and then complete one set of each. As you continue to do these exercises over time, add more weight; add a 2.5-pound weight plate on each end and then move up to a 5-pound weight after a few weeks. The proper amount of weight for you will make the last few repetitions of your set difficult to complete.
If you're looking for equipment that you can use at home to help you build muscle in your butt and thighs, buy a set of dumbbells. You can build muscle in your butt and thighs by holding on to the dumbbells as you perform stepups onto a stair stepper, front lunges, squats or dumbbell deadlifts. Try variations on the lunge to work different parts of your glutes, such as crossover lunge, or hold the dumbbells as you do lunges while walking up a flight of stairs. While the dumbbells don't work your legs specifically, they do add more intensity to the exercise.
A stability ball -- often called an exercise ball -- is another piece of equipment you may find in your local gym or that you can buy for your home. Exercises that work the glutes include the stability ball shoulder bridge, in which you place your shoulders on the floor and your feet on the ball and alternate raising each leg. The stability ball hamstring curl can also work your butt and thighs. Place your shoulders on the floor with both of your feet on the ball and your knees bent. Slowly roll the ball out until your legs are straight and your calves are resting near the top of the ball.
Nicole Vulcan has been a journalist since 1997, covering parenting and fitness for The Oregonian, careers for CareerAddict, and travel, gardening and fitness for Black Hills Woman and other publications. Vulcan holds a Bachelor of Arts in English and journalism from the University of Minnesota. She's also a lifelong athlete and is pursuing certification as a personal trainer.