Mark it once you can do it without this page open.

How to do it

  1. Hold the stud finder flat against the wall, press its button and let it calibrate before you move it.
  2. Slide it slowly sideways, mark with pencil where it signals the first edge, then keep going and mark the far edge.
  3. Put a small mark at the center of the two edges; that is where your screw goes.
  4. Measure 16 inches from that center to find the likely next stud, and confirm with the finder.
  5. Without a finder, look for an outlet or switch: the box is usually nailed to one side of a stud.
  6. Knock along the wall with a knuckle; the hollow sound turns dull over a stud.
  7. Run a strong magnet along the wall to find the drywall screws, which line up over studs.
  8. Confirm by pushing a thin finishing nail through the drywall where the shelf bracket will hide the hole.

Common mistakes

  • Moving the finder before it calibrates, or calibrating it over a stud.
  • Marking only one edge and screwing into the edge of the stud instead of its center.
  • Assuming every wall is 16 inches on center; some are 24, and corners and windows break the pattern.
  • Driving a test nail where a pipe or wire could run, such as straight above an outlet.

Quick self-check

Three questions. Your last score is kept in this browser.

1. Why start a search near an electrical outlet?
2. Where should the screw go once you have marked both edges?
3. What does a magnet slid along the wall find?

Teach this to someone

A one-page sheet for showing a friend, a roommate or a kid: what to say, what to show, and one question to check it landed.

Words on this page

Last reviewed . First published .