Remove the drawer. Position the frame section of the 24-inch full extension drawer slides against the frame of the drawer, on the bottom corners. Set a carpentry level on top of the slides to make sure they're straight and level. Mark the locations of each of the attachment screw holes against the drawer's frame.
Drill out each of the marked positions, being careful not to drill all the way through the wood. Reposition the frame section of the slides against the drawer frame so the holes line up. Set the included screws or 3/4-inch wood screws within each hole and tighten them halfway. After all the screws have been installed, tighten the screws completely.
Pass the other half of the drawer slides into the installed sections, and leave them fully extended. Slide the drawer into its position. Mark the locations of the drawer slide attachment holes on the side of the drawer.
Drill into the drawer at the attachment hole locations, preventing the drill bit from going all the way into the interior of the drawer. Set the included wood screws or 3/4-inch wood screws into the slider holes and into the holes in the drawer. Attach the screws in place by drilling them in completely as in Step 2.
Test the operation of the drawer and make any necessary adjustments for complete and smooth operation.