Barbell squats

Stand under the barbell and position the bar on your traps or rear delts.
Grip the bar a little wider than shoulder width, and make sure your elbows point in the same direction as your torso.
Lift up the bar and take one controlled step backwards to avoid hitting the barbell rack when doing your reps.
Plant your feet shoulder-width apart and angle your toes slightly outwards.
Optional – Elevate your heels on a pair of plates to increase mobility.
Flex your core.
Breathe in and start bending your knees in a controlled manner for 2-4 seconds. Imagine that you’re trying to tear an A4-paper in half with your feet to avoid buckling knees. Your knees shall always point in the same direction as your feet.
Pause at your deepest point of the squat.
Push your feet through the floor and extend your legs to the starting position (90-95% straight). Breathe out when you reach the halfway point.