Stand with a stance which is slightly wider than Sumo stance, with toes pointed out.
Breath in and engage the core and keep your back upright.
Shift your bodyweight on one leg while simultaneously lifting the toes up of the other leg.
Squat down with the loaded leg as low as possible, while keeping the other leg straight.
Drive through the loaded foot and come back to the starting position and breath out.
Breath in and repeat the movement on the other side.
You can take support with the hands while trying Cossack squat for the first time.