Long time no posting but here's a quickie.
Step 1: Materials and Tools
Cheap, neoprene mouse mats. I payed about €2 each.
Snap buttons with tools. I payed about €8 for a set of ten buttons with tools.
You also need a hammer and something to make a hole with.
Step 2: Add Snap Buttons
Follow the instructions for your set. Add the snaps in pairs to each corner of the mat. I put mine about 20mm from the corner and 15mm in from the edge.
Step 3: Snap Together and Roll Some Dice.
That's it. About an hours work for four.