I feel like the village idiot: How do I create a vault?

I've seen many suggestions, and searched by recent in this sub, but everything seems outdated based on the version of the Reddit mobile app. I've also read through the Moons wiki. I generally see the idea that I need to do something that involves a blockchain transaction in the app to trigger vault creation--but how can I do this?

Is it possible to create a vault in the mobile app at the moment? I've clicked all around the mobile app and on Reddit in my browser without any luck. Thank you kindly ????