How do I put my clay d20 together?

I'm making a clay d20 for my boyfriend's birthday, and all I've managed to do is make twenty decent-sized triangles for it. I've looked at patterns online, but most of them are for paper versions and I'm getting quite frustrated trying to translate those into clay form. I was thinking I would make it hollow, and just piece the triangles together, paint it once it dried, and then Sharpie the numbers on since I don't trust my ability to paint them on. So far, though, it hasn't worked out that way. Should I attempt to piece them together, or scrap it for a solid piece?
For further information, I'm using something called Creative Paperclay that I found at AC Moore. It says on the package that it's air dry and normally takes between one and three days to dry depending on the density of the project (which is why I went for a large, hollow d20 instead of one that I could actually make into a functioning one).
Prompt help is very much appreciated, as his birthday is tomorrow and I've been working on this thing for days with no luck. Thank you!
Asked Nov 28, 2013

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