Ok this looks simple but it actually is XD.
There are bunch of way to store keycaps when you dont have it on your Keyboard.
You can have a small collection in a 3x3 stand or buy those switches little tester linked to a keychain.
This concepts have those options in mind and lets you have your Keycap in a personal stand that can be used as a keychain if you add the ring for it, can be used as a fidget toy, maybe even an anti stress toy or just to show off your collection.
What do you think?