Place the table in the desired location. Mark the table legs or base with chalk or pieces of tape.
Set the brackets in place. Position the brackets toward the inside of the table for reduced visibility of the hardware. Mark the bracket holes with a marker. Remove the brackets.
Drill pilot holes at the marked locations on the table legs, using a traditional drill and a wood drill bit with a slightly smaller diameter than the bracket screws.
Drill pilot holes at the marked locations on the concrete floor, using a hammer drill with a carbide-tipped drill bit with a slightly smaller diameter than the concrete screws. Start the hole using a slow drill speed, then increase the speed as the hole becomes deeper.
Replace the brackets, lining up the screw holes with the pilot holes. Drive the bracket screws through the screw holes and into the table legs or base. Drive concrete screws through the remaining screw holes and into the concrete.