This is a great variation of the front squat that allows you to hold the weight in a more comfortable way than with a barbell. It will also work your shoulders, because they have to stabilize the weight.
Begin by cleaning two kettlebells to your shoulders and catch them so they are comfortably resting on your shoulders. If you do not know how to perform a kettlebell clean, you should learn that first. Next, get into your squatting stance that you would use for barbell front squats. Then, squat down by pushing your hips back and keeping your back straight; it is important to look forward throughout this movement and not allow your body to loosen. Continue to squat down as far as you can and then pause slightly at the bottom. Push through your heels and bring your body back up to the starting position. Repeat this movement until your set is complete.
You should master both the kettlebell clean and also the barbell front squat before you attempt this movement. It is a great variation but you should be careful and start with light weights.