All I did was set the crayoning with a hot iron, with a paper towel between
to absorb any excess crayon/colour.
I tried the technique on a mug rug ... and just toss it into the wash, without any thought.
The colours have "stuck" well .... though the mug rug is looking quite sad, with all the use!
It served it's purpose before I tried something bigger and more serious!
Probably I'll combine it with hand embroidery when I make that "real" project!