Don't be fooled. This is not easy.
Here are some tips:
Keep your stomach pulled in throughtout
Weight is in your heels during the deepest part of the squat
Your tailbone is tucked under duringthe deepest part of the squat
Shoulders over hips at full extension, don't lean back
Elbows as high as chest if possible, but be guided by your lower back arch and shoulder fexibility
Elbows stay out over the bar, rather than forward