You need a laser printer, packing tape, and a couple of minutes.
This will not work with ink jets, only thermal toner, or indelible ink based products.
Step 1: Make some designs and print them !
The white (paper) is removed later so it is clear.
I have found that the worst quality paper makes the best decals.
This only works with thermal - non water soluble printers like a laser printer.
Most copy machines use thermal ink.