There are a few materials that will work best, depending on what type of floors you have.
-For a thick carpet, use velcro. Either get a few 4"x5" pads (one for each corner) OR 12' of 1" wide velcro strips and put it along the edges. You'll have 12" extra if your pad is standard sized; use it to make a 4"x4" box in the middle of the pad
-For a thinner carpet, your best bet is actually just to staple a 33"x33" pad of similar carpet to the bottom of your pad upside-down.
-For linoleum, hardwood, or tile, you'll want to use some kind of rubber stopper. You can get little 1/2" rubber feet that stick on at home depot, lowe's, or any hardware store for something like $2 for a pack of 12. If you just get 36 of them, you can stick them one the bottom of the pad, right under where the screws go.
If you're playing on smooth concrete (ie in your garage or something), your best bet is to just make your pad heavier. Nothing really gets great traction on smooth concrete. A good solution for any surface is to get some of the rubbery foam mesh that is designed to be put in drawers and kitchen shelves to prevent things from slipping. I can't remember what it's called but it works decently on pretty much any surface.
Even arcade pads don't prevent slippage by weight alone. The 2" feet are what prevent sliding. Unfortunately, a 3/4" plywood base will crack if you elevate it on feet.
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I used to be active here lol