I have a bunch of cardboard boxes I'm cutting up for the biggest boards. the smaller ones are cardboards (8.5" x 11") that come out of paperwork from the print shop at work. our secretary saves them for me. I cut them in 1/2 for the mid sized lengths (1 yd to 2.5 yards) the smallest ones are those same cardboard cut in quarters (for 1/2 yd lengths)I have a bunch of 4 yard and up lengths that I got the empty fabric bolts from Hobby Lobby and WalMart to store them on. (not shown)