Clean off the top of the fridge. There will be metal shavings from drilling. You don't want to scratch your fridge, do you? Now place the tower over the hole and center it so that it looks good to you. Use a visible marker and mark through the screw holes on the tower. The bolts I used to secure the tower down are 3/16th x 3" bolts. Use a drill bit slightly less than 3/16th to do your pre-drilling. Drill all the way through on three of the holes. On the fourth (note the picture), only drill until you get through the metal.