Attaching badges to uniforms is something that is definitely outside of my wheelhouse, and while there’s apparently the option of having it done at the scout shop, I’ll attempt at least to do it myself.
My wife originally took on that responsibility and used Badge Magic, but as my daughter joined and my son has grown I’m looking to do a shirt swap which involves moving the badges around.
This video from Badge Magic provides guidance. Though they seem to recommend Goo Gone over Goof Off, the video itself uses Goof Off and getting the right formula of the former seemed less obvious, so I picked up some Good Off and the badges easily came off.