First you will need to find or make a template. Commercial envelopes are usually folded from paper shaped like a long diamond, but to make use of magazine pages you will need the kind that is closer to a rectangle with tabs on the sides. Look through your mail and see if you have received an envelope that you can use as a template. Carefully unfold it and see if it fits on a standard magazine page. You might be able to make minor adjustments to make it fit.
Trace your template onto the magazine page and cut it out. Full page magazine photos are very pretty. You can also use old maps and posters. A fine red pen will be visible on most pages to allow you to trace your template and cut. Fold the edges of the side tabs and bottom neatly following the pattern of the envelope you are using as a template. Glue the side tabs to the bottom flap with a permanent glue. A roller glue pen is very convenient for this and avoids globs.
For the top flap of the envelope use a children's non-toxic paste glue. Fold the edge over the upper flap and re-open, apply paste to the edge where it will overlap with the envelope, and allow the paste to dry with the flap open. This makes the envelope lick-able at a later time.
Place a white self-adhesive address label on the front of the envelope to make addressing clear. You can make your own labels by cutting out white rectangles from received mail and using the permanent glue to affix to the front of the envelope.
One or two dozen hand made envelopes make a nice gift. Tie together with ribbon or cut a strip of magazine paper long enough to make a collar to hold them together.
