Step 1: Supplies and Ideas
1. A piece of cardboard, thick posterboard, wood, etc. for the actual collage (Make it bigger than you think it'll need to be; once you start getting out the supplies, you won't be able to stop!)
2. A container of dry-clear, secure glue (I used Elmer's)
5. Ribbon, fake little flowers, nice stickers, etc. (optional)
6. Craft paper/some kind of background paper (preferably varied, but you hopefully won't see it much anyway)
7. Decopauge glue (optional)
9. Assorted memorabilia.
For that last one, you can get pretty much anything you can think of that has some meaning to you or your collage recipient, as long as you're sure it'll look good (and stay on) the collage. I used scraps of old clothes, childhood artwork, pictures, postcards, childhood poems, and cute things I used to say typed in cool fonts and cut out. These are only a few of the things you can use, and it all depends on what you think the collage recipient will appreciate the most. I made mine with as much slightly 3D stuff as possible, to catch the eye as it goes across the paper. Be creative!