Here's where I got the idea from: http://mademoisellechaos.blogspot.com/2010/03/make-your-own-seed-bombs.html
I found it best to just use my (old) blender, and I put in about 7 magazine pages, 2 sheets of tissue paper (for a prettier color), and 2 cups of water. I blended it up, added seeds, blended a little more. Then I poured it into my strainer to get out the majority of water and squished it into a big ball, getting out as much water as I could. I then split it out into little balls (about the size of a marble) and left it to dry. Drying took decidedly longer than I was expecting, a few days, at least! I'm excited to try them out, and I hope you are too!