Set Up the Barbell
Place the barbell around the shoulder height down on the squat rack. Verify that it is securely fastened. If you are unable to finish a rep, raise the safety bars to a height where the barbell will catch. Put the right amount of weight on the barbell for your level of fitness.

Position Yourself Correctly
Grip the bar with hands negligibly wider than shoulder-width separated as you foot under it, positioning it on your upper back preferably than your neck. To remove the bar from the rack, stand up straight, take a step back, and place your feet shoulder-width apart.
Perform the Squat
Decrease your hips down as if you were posing in a chair, maintaining your chest high and your body taut. Lower yourself until your thighs are parallel to the bottom, then introduce yourself back up by plowing through your heels. For the required amount of duplications, repeat.
You may use a rack to perform squats securely and actually by following these procedures.
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