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Once the mounting points are marked, use a power drill to create pilot holes. The drill bit size should be slightly smaller than the diameter of the screws you'll be using, allowing the screws to bite firmly into the wood stud. For tiled walls, like those seen in the video, you will first need a specialized tile bit (diamond-tipped or carbide-tipped) to carefully drill through the tile without cracking it, then switch to a standard wood drill bit for the stud. Drill to a depth slightly less than the screw length. Drilling pilot holes prevents the wood from splitting and makes driving the screws much easier and more secure.