Digital BW, The Print

Perhaps I should have been more specific with my original question.
For some prints I favor printing on a paper the full size of the
frame, the image itself being somewhat smaller and outlined with a
very narrow border, creating an illusion of depth. In PS terms, the
canvas is bigger than the image, the exposed edges of the canvas being
a pseudo-mat. Being something of a novice (obviously!) it seemed this
could be accomplished by simply dropping the print into the frame sans
mat, but this of course puts the print in direct contact with the glass.

Given that context, what is the best way to accomplish what I'm after?

Also, would someone care to briefly explain 'face mounting' as used
earlier in this thread?

Many thanks...