Well, okay, here goes ... it's fairly simple ...
1. peel the onions (I have done this with both yellow and red onions and found that the reds will sometimes come out with blue and green dye spots)
2. boil the skins only, you can do them separately, or together in the same pot.
3. while still relatively hot, spread the skins onto a good quality watercolor paper then lay an additional sheet on top and press. I use two full 12 packs of soda. Then, I sort of forget about them.
4. A day or two later, when completely dry, separate sheets and discard the skins.
5. Now I usually cut them into ATC size and mount them on a 9x9 sleeve and stare at them until I see the images I want to bring out.
I've attached an example of three cards I finished this way, and like I said, it's such fun just creating. For those who do collage, they also make some awesome background cards.
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