Long weekend...sunny out...I may have gotten a tan from the lightable. Nice area, isn't it?
I've discovered what works best for DOING MULTIPLES; first spend 2 days creating guidelines. Not necessary, but it helps, especially when you're in a hurry. OK. For addressing envelopes, draw guidelines in pen on tracing paper. Want perfection? Use the Ames lettering guide. Trim tracing paper so it's bottom edge lines up with the bottom edge of the envelope. Fold the bottom edge of a wide sheet of paper over about an inch. Find the sweet spot on the table, which is directly in line with your eyeballs if you were to lean over and touch the paper with your nose. Tape it to the light table. No, not your nose! Set the guidelines in the pocket and tape in place. Now you can slip your blank envelopes into this pocket & get them perfect every time. Not the lettering, that's a different story; perfect envelopes, dummy! You don't even have to tape them! Tape paper around the rest of the area so the light doesn't hurt your eyes.
PROCEDURE: Blank envelopes & response cards on the left. Ink & pen on the right. List of names standing (or sitting, but in a book stand) in front of you, with a sticky note on it placed under the name you'll be working from. Pick up blank envelope with left hand, set into pocket. With right hand pick up pen, dip into dinky dip (perfect 'cause you can't dip the nib in up to your elbow!) of ink, letter (it helps to turn the light table on), put pen down, pick up finished envelope with your right hand, place it on your right while picking up the next blank envelope with your left hand. Works great.
If you're lettering with gouache you'll need to brush the gouache on the nib so that's a whole other deal. I always try to convince the client to go with brown so I can use walnut ink.