I used the highly popular hockey puck idea. I bolted them to the bottom of the compressor footings only, not into the cement floor. I recessed the bolt heads through the bottom of the puck and up through the footing and capped off on top with the washer and nut. By mounting the pucks to the compressor only, I'm still able to lean and "walk" it around a little when needed for cleaning or service. There's no chance of mine falling over because mine's in a ventilated closet, but for those with concerns, it could easily be tethered to the wall.