Use a variety of rep ranges and sets. It's safest to squat until your upper legs (from knee to hip) are parallel to the floor. However, at times you can squat past parallel, provided the poundage you use is light. Also, with light poundage you can vary foot placement and foot width to further target other areas of the upper legs.

Further extend the traditional squat by adding pile squats to your program. Pile squats can add some variety and help target the muscles of the inner and outer thighs to a much greater degree.

Reverse Partial Squats

The strongest range of a traditional squat is from the last few inches to contraction point (standing upright). Therefore, if you want to work the weakest range, then that would be from it's stretched position (squatted position) to roughly mid-point.

To ensure safety on this exercise, you should perform these either with dumbbells or in the squat cage. Set up the safety rails in the squat cage so they are just below the barbell when you are in your full squatted position. You don't want the safety rails to touch your barbell as you squat, but it's there just in case you can't complete your set or you lose your balance.

Lunges are great for working all the muscles in your upper legs and glutes. This is an essential exercise, yet often neglected. Lunges can be performed in a variety of fashions such as walking lunges, reverse lunges, side lunges and so forth.

The stepper is a great way to get cardio in, as well as build and shape your legs and glutes. The stepper requires you to use your legs and glutes to move the foot platforms up and down.

To build great buns and thighs you need to incorporate exercises that use those muscles to a large degree. Compound exercises should compose the bulk of your training. When you build your buns and thighs to their maximum potential, you wont' think twice when someone calls you a hard ass.