1: Screw the floor: Try to externally rotate your leg without changing your foots position on the floor, you should feel it in your glutes before squatting if you’re doing it properly
2: Brace the core: A strong core is key to every lift, make sure you breathe into your stomach and not your chest.
3: Bend the bar around your back: Not getting enough back tightness is one of the biggest mistakes lifters make in the squat. Try and pull your elbows into your lats.
Using these cues can help you achieve full body tightness and make the weight feel lighter on your back. Make sure you practise these cues while warming up and not just when the weight gets heavy.