N.B.
My daughter was 4 when we had to do her's, so a big age difference. But we did silly things with hers. But she had to wear hers all day (but sleeping) for 3 days on, one day off. She only had it off for night sleeping.
We drew silly things on her's. Sometimes it was a funny eye. Othertimes just drawings. Often we let her do it (but she was older than your son). It made her more invested in it. Sometimes we added stickers to it (I got some decent teency ones at the craft store that we experimented with that actually stayed stuck to it...stars, hearts, snowflakes and the like). It made her a bit invested in the process. But a patch, with glasses over it for her for many months was the norm.
She also patched her doll, and her favorite Beany Baby (her "lovey" all her life). We just had to get creative cuz she had to wear it so much for so long. And it worked, she just got used to it.
We "wasted" alot of patches and those little round bandaids (for her beanie and her dolly) but it helped a ton!
Best wishes!!