Styles and then Keyboard shortcuts

Recently on a Capture One online tutorial there were instructions on how to create all the masks for "People", save them as a Style and then create a custom Keyboard Shortcut. This has worked brilliantly and with two keys (mine are Shift + X) I get everything. I then can choose to use the mask I want without any more wasted keystrokes. What I'm now trying to do, is the same thing with Background and Subject. Generally if I use Background, I'm pretty sure that I'm going to use Subject as well (and, duh, vice versa), so why not have it there waiting for me? The problem is that I can't figure  out how to do this.  Thoughts?