Step 2: Sensitizing (making it "film")
Basically, you're making old-school film here. All modern film is based on the principle that silver halides are light-sensitive. What's a silver halide? Go ask Google. Simply put, exposing the silver plate to Iodine vapor in a darkroom turns your shiny silver plate into a heavy-ass hunk of film. Get it? The plate IS the film, therefore there is no negative, therefore this is a unique piece of art. No editioning of prints here.
My sensitizing box is made out of poplar, glue, Pyrex(C)(TM), and Lexan(C)(TM). The Iodine crystals go in the glass dish and, when not in use, the Lexan slides over the top of the dish to keep the corrosive fumes from turning various metals into various powders. Don't inhale Iodine fumes, quite exciting and dreadful things happen to the color and composition of your respiratory system. The Iodine crystals never get used up in this process. Just buy enough Iodine to cover the bottom of the glass dish that you're using and you'll be set for a long time.
You slide the polished plate face-down over top of the Iodine crystals. Depending on temperature, humidity, astrology, and voodoo, the plate will turn a pretty rosy purple after a minute or two. Every 20-30 seconds or so, I pull the plate out of the sensitizing box, flip on a light, and look at the color of the plate.
Why doesn't this screw up the plate? The ISO of a Becquerel Daguerreotype is about .0004. To fix the issue of exposing the plate to white light in the darkroom, just cram it back in the box over the Iodine for another 15 seconds or so.
Once sensitized, load the plate up into any ordinary modern film holder.
Because I'm tired of searching eBay for photography arcana, I have just reverted to taping the daguerreotype plates on to the septum of the film holder. Not very classy, I know but it works. I'm sure you can figure out a way to mount a silver plate to a film holder!