What you'll need:
1. Armor Etch glass etching cream, or a similar product
2. Blank adhesive stencil sheet (or vinyl adhesive shelf liner paper)
3. Soft craft board or cardboard to cut on
5. Small brush
6. Design you want etched (my fiance made a "duo"-gram for us with both of our last initials)
7. Rubber gloves
8. Something glass to etch
9. A VERY sharp knife - exacto-knife, craft knife, scalpel, etc. I picture an exacto-knife here, but I ended up using my mom's craft knife.
10. Masking tape
11. Pen & carbon paper (not pictured)
12. Running water, glass cleaner, & paper towel
Step 1: The Stencil
Step 2. Cut out your design with a VERY SHARP craft knife. Remember you must cut it in negative - the "holes" are where the etching will be! To keep yourself on track, keep a printed copy of your design nearby - coloured spots get cut out, and white spots get left behind. Remember to leave a "connector piece" to any otherwise isolated chunks (e.g., the hole on the inside of a capital A). (If cutting on shelf paper already stuck on your glass, careful not to cut too deep!)
Step 2: Etching
Step 4. Dab the etching cream over the stencil with the brush. I found brushing left it too thin, I recommend dabbing. It needs to be thick enough that you can't see your stencil shape through it. I appear to be a bit thin in spots, but it turned out okay.
Step 3: Rinse & Clean!
Step 6. Remove the stencil, clean glass with any glass cleaner product, and dry.