There are about a dozen different ways to do that, but I have had good luck with vacuum bagging veneer. I made the pump out of a cheap Chinese electric tire pump. I removed the case and moved the hose from the "out" side to the "in" side and viola!, a vacuum pump. I bought a vacuum bagging kit form the big auction site, and have already done two of the 4 parts of one of my treadles.
Not hard, just time consuming
I have no real good pics, but will see what I can find and post later