When I did mine I colored very heavily with the crayons then put between two sheets of waxed paper for heat setting with a dry iron (no steam!!!). Then did outline stitch embroidery around the flowers.
Lasted over 30 years worth of regular use before the muslin started splitting in the non colored areas. It had been started for my moms hope chest in the 30s and I completed it in the 60s. Finally had to quit using the quilt in the 90s.