First off, I don't know how you got the idea that I'm saying go to failure each day. You go as long as you can, until you reach 1 minute. That happens pretty quick, and while it will always burn a little it is relatively easy after a month or two, and that's the whole point. You have to get your body used to using the right muscles for walking.
As for ACTUAL squatting for the purpose of athletic training, the rule on foot angle is that the gap between your big toe and the one next to it should be in line with your heel, which in turn should be in line with your knee, which should also be in line with your hip joint. If someone took a picture of you in your squat while standing in front of one of your feet, you should be able to draw a perfectly straight line with a ruler through your big toe gap, your heel, the center of your knee cap, and where the ball of the femur connects to the pelvis. If you can't draw that line, your stance is wrong. You can use a mirror to figure that out yourself pretty quickly. You will find that the angle changes some as you widen or shorten your foot width.
The wall squat that I recommend for helping your body re-learn proper motor patterns is not a squat for the purpose of athletic training, and it is not free-balancing, so it does not follow those rules. Also, for best results you will need to actively practice walking properly for a few minutes at least once a day.