I do six sides every time. I have the time considering it is usually one or two balls at most. Weather just touching up one surface or doing layers at 30secs a side I have the time.
The other reason I do six every time is in bold below. How accurate it is I am not sure but if you have the time why not use it.
6 Sided Method
1. Mark a reference dot or line on the outside of the spinner bowl.
2. With the reference mark always toward you, place the ball in the spinner with the label of the bowling ball facing up.
3. With the reference mark facing you, rotate the ball 180 degrees toward you, the label of the bowling ball will face down.
4. With the reference mark facing you, rotate the ball 90 degrees away from you, the label of the bowling ball will face you.
5. With the reference mark facing you, rotate the ball 180 degrees away from you, the label of the bowlng ball will be away from you.
6. With the reference mark facing you, rotate the ball 90 degrees to the right, the label will still be away from you.
7. With the reference mark facing you, rotate the ball 180 degrees to the right, the label will still be away from you.
Note: All 6 sides the ball are now resurfaced evenly.
4 Sided Method
1. Mark a reference dot or line on the outside of the spinner bowl.
2. With the reference mark always toward you, place the ball in the spinner with the label of the bowling ball facing up.
3. With the reference mark facing you, rotate the ball 180 degrees toward you, the label of the bowling ball will face down.
4. With the reference mark facing you, rotate the ball 90 degrees to the right, the label will still be away from you.
5. With the reference mark facing you, rotate the ball 180 degrees to the right, the label will still be away from you.
This 4 sided method should only be used for cleaning and other non-surface altering projects, as 2 "sides" of the ball are not covered.
Note: Using the 4 sided method for surface alterations will eventually leave a ball out of round