[header] How to make an envelope advent calendar [title] Choose some paper for your envelopes. [step] You can get really creative here. You can use the same color and pattern for each envelope, or you can mix-and-match. 
You can use solid-colored patter, patterned paper, or even double-sided paper. Scrapbooking paper is great for this, but so are kraft paper, old book pages, wrapping paper, and origami paper.