I have sold country themes ,outhouses,toilet paper with men sayings on them.just to name a few
Men are hard to do, if it is too heavy a design they complain the towel is hard. If I do a light design I hear it looks like it is for a girl. I would do towels that are a medium color so the stitching will show up. Using white on a navy did not go over well at all. I have found that Mr. - Dad,- Oorah - His - King - Mine work well. If they have a Harley motorcycle - Live to Ride and Ride to Live are big. Geek is good, Nerd is not; For a science teacher, I would use Scientist or a number and symbol from the periodic table. It depends on the part of the country too. In Boston you could use Snowman, in California you could use Surfer or Hang Ten.. Good luck - I think deciding what to use is the hard part.
jane
What about a dragon my son in law is a fan so I always do dragons for him
How about Words like Head & Feet on one towel. Maybe words that describe a man. Dad, Daddy, Masculine, Handsome, Bald & Beautiful, Prince Charming, Faithful, Honest, Courageous, Dependable, etc.
You can always google "word to describe someone".
Be careful about being negative.
I'm with Sarah...cars, golf designs...and also motorcycle designs...
I usually embroider old cars or golf designs if the person plays golf. Good luck with your show.