During a weekend away, I hand-stitched nice dark denim over some holes in Luke's jeans. You need to be relaxed, not under time pressure to enjoy doing this.
Just fold the edges under of the patch fabric so they won't fray, pin, and watch TV or listen to a radio show. (I watched a great Indian movie that I hadn't expected to like!) The letters are sewn with a large needle and wool/yarn.
If you take a positive spin on holes worn in knees (in otherwise strong jeans), they stop being problems and start becoming opportunities.