You will need:
* Access to a laser cutter
* Note cards and envelopes. I used 3x5 cards. You can find them at an art store like Blick, Utrecht or Flax. Lighter colors will generally give you a subtler contrast to the monogram and darker colors will produce a stronger contrast.
* ~20 small weights (I used sections of T-50 staples)
* Painters tape
* Blank newsprint or butcher paper
Step 1: Design Your Monogram and Etching Template
Begin by creating outlines of the cards and envelopes of the appropriate size. The outer dimensions of your cards should be listed on the pack. I used a caliper to measure out the flap on the envelope. Create your desired monogram graphic in the desired location on the card and envelope. I would suggest making the card and envelope designs different colors so you can set a different laser power. When you're happy with the result, copy it in a grid so you can etch multiple sets at once.
Step 2: Etch
Run a series of tests on your cards and envelopes to dial in the power settings correctly. The paper is relatively sensitive to laser settings -- too much power and you can easily burn through. Note that the settings will depend on the weight and composition of the particular envelopes and cards you use. You may need to adjust settings for different colors, cards and envelopes. I found the following speed/power settings and line weights worked best:
* Whitish: 80/30 2pt lines
* Red/Green: 80/25 1.5pt lines
Envelopes (all): 80/15 2pt lines
Finally, lay out a full set of cards and envelopes on your template. Use small weights to hold down the flaps on the envelopes. You may also want to use small weights to keep the cards from moving if you have air assist on. Run your etch and repeat for as many cards as you want!