Finally done! Sorry for bad pictures... >.<
Found this backpack at Big 5, and thought it was the perfect color and design for a Portal backpack...and here's the result!
All Portal pictures on the bag were made by me. I don't own Portal though lol...
1. drew the designs on Paint Tool SAI and Photoshop CS4
2. Print out on T-Shirt or Fabric Transfers. (DARK tranfers for dark backpack!)
3. Cut out shapes.
4. Iron on.
Hope you like it!~