These are all good advice, and mostly not overlapping.
Release you perineum, let your weight drop through your knees into your feet, don't let your knees go past your feet (maybe not much past your ankles), have your knees pointing in the same direction as your feet, take your weight off your foot when you're turning it, respect your capacities.
Speaking from experience, you can't necessarily trust that you have an accurate idea of what you're doing with your knees. A mirror, a camera, a teacher, and/or humble efforts to increase awareness are good ideas.
The kwa is the fold at the hip.
I would rather have had the videos visible in my post, but neither embed media nor rich text were working-- and the only way I could preserve my line breaks was to disable auto-formatting.
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