Regarding the circle walking the circle can be very tight but if too small you might get dizzy. You can think of the circle size down in our oak trees as the ideal size and adjust from there as to what works for you. For most benefit walk for about 40-50 minutes. Spend a few minutes at the start to organize the qi field (OTQF), turn right and walk in that direction for about 10 mins, then change directions for another 10 minutes. Repeat both directions so that you do both directions twice. At the end spend about 5 mins conserving qi. You can use any music you like. In the beginning it is easier to use music that has a natural 4/4 rhythm but if you don’t need that you can pick anything you like. Also in the beginning you can walk for 30 mins and work up to 40-50. The most important part is OTQF and conserving qi at the end.