(Because you are going to be shirring this--it does help if it is a CHEAPY towel. The expensive ones are too thick and won't shirr as well. SEE--it PAYS to be cheap sometimes!)
Sew about three forward stitches and then back stitch about three and then continue sewing the length of the fabric.
If it isn't as tight as you want it--you can take it to your ironing board and spray a little water on it and PRESS it with lots of steam. The shirring will shrink up together nicely. Its quite neat to see actually!
Now on to the straps.
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