I prefer screws to velcro, it's much more secure. I use the metal strapping that has holes in it (found at any hardware store). Just cut off a few pieces and fasten them on the pedal using the screws on the bottom. Then you have some wings you can screw onto the pedal board. Some people also use bike chain links the same way, but those might not work depending on the position of the screws on the pedal.
