Greetings -
I didn’t want to hijack the Song Keychain - Looking for Tips thread so thought I’d do the writeup here.
First Attempt - I engraved on the back (in reverse) then with the masking still on, flood coat the engraved part with Black fingernail polish, wait to dry, then peel the masking. Came out ok, but the tiny letters are hard to read for song title and such, but it worked ok.
Round 2 and 3 - The teal one I just engraved on the face and it has enough contrast to work fine and is much less work. But it seemed too big so I made the pink one to reduced the size a little.
But I think the fourth version is my favorite. I just engraved HD Graphic on the front of the medium clear acrylic and attached the photo like the others.
For the photos, I printed on an avery label, made a jig when cutting out the main piece, and added a ‘score’ square where the photo goes.
Peel the square where the image goes, apply the photo (label) but leave the masking on the rest of the piece. Place the item back in the jig, (just) score again to cut the edge of the label, then peel everything. Works pretty well.
I think this method is pretty easy. Although it does take 11 minutes to HD Engrave the graphics, so that’s a consideration if you’re doing a ton of them. And It’s just a paper label so it won’t be a round for a long time, just a good time. 
If you have access to a color laser and a glossy label, it would be more durable.
Notes -
The song graphic isn’t a Spotify link image, it’s just a graphic I grabbed online, flipped and reversed it for 4 variations and copied them together.
It would be pretty easy to pre-make a bunch of these and leave off the ‘Wrecking Ball’ song title line to allow people to add their own favorite song. So long as you make a jig, you could engrave that with their own request, along with scoring the photo, so they are customized a little. Just a thought.
HL