I have been asked what the stitches look like. When a yo yo is small, close to that of a USA quarter, then I do about 6 stitches (pretty much in one spot) and travel with needle and thread inside the yo yo to the next spot to stitch. That saves a lot on starting and stopping of the thread.
On bigger yo yo's, I stitch as I do when doing English paper piecing joins. This makes for a join that is anywhere from 1/4 and inch long to about 1 inch long, the size of the yo yo determines how long this seam is. I also like to go over the seam two or three times because the openings in between the yo yos mean they get snagged and pulled more and the stitches are more likely to tear out. See below pictures for examples.