I used a heavy piece of black fabric, mine has a tone on tone vertical stripe, and wrapped it around a piece of foam core display board. You can just duct tape it to the back. I also duct taped some wire back there to hang it. Then I bought ahpolstery tacks and just used them to tack my doily to the board. I thought about starching the doily to keep it flat and attached to the board, or glueing it somehow, but it's been fine for a couple years now. The biggest problem is keeping my display dust-free, since it's not in glass. But it Works for Me! Here's a shot of my project on the wall at a time when my kitchen was relatively clean.
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