How do I set up a MetaMask digital wallet for my collectibles?

You can download the extension here: Metamask for Google Chrome.  There are many step by step documents, here’s one that we created, but please refer to Metamask’s own site, in case the process has been changed.
https://medium.com/emusic-official/the-emusic-guide-to-buying-crypto-88b2d64bc55

You can also watch this step by step MetaMask video that provides an overview of how it works: https://www.youtube.com/watch?time_continue=8&v=6Gf_kRE4MJU