Hi, Rita,
It is a good idea to wash towels before embroidery. Since towels are made of cotton, they can shrink; some substantially. We do not believe the use of fabric softener will in any way effect the embroidery. A low tack iron on tear-away stabilizer will work for any thickness of towel. And a water soluble topping is always advised when dealing with a loft fabric. The thickness of the towel is really not of concern.
Good luck with your new "toy"! Let us know if you have any other questions.
AnnTheGran Support
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