You can print the forms directly from Kayak Foundry. Since my printer only takes legal-size paper, it gives you most of the forms on several sheets of paper. with little target-shaped registration marks.
I used push pins to align the marks, and taped the pages together. Some of the biggest forms require as many as six sheets.
I used 3/4" MDF, and very stinky contact cement. All the forms fit on half a sheet.