Make Harry Potter shrinky dinks. I just used permanent markers and drew silly pictures and then just followed the directions on the package. Remember they will shrink down to be about 1/4-1/3 the size. Set aside. I like to put different Harry Potter icons like the snitch, Hogwarts castle, rat, glasses, characters etc. and I like picking beads and buttons that represent the different Hogwarts house colors and animals.
Fold the main fabric in half and iron in place. Tape the vinyl to the middle of one of the sides of the main fabric. Attach and fill the I Spy pouch like described above.
Assemble the I Spy Bag according to these I Spy Bag directions. I will be updating this with a condensed video tutorial but until then I have a live video you can watch step by step pictures here.
Cut "Revelio" out of iron-on vinyl (I used my Cricut explore 2). If you've never done that see my full iron-on vinyl tutorial.
Iron it on.