- 1). Place a piece of paper in between the micrometer's measuring jaws, then close the spindle -- the technical name for the lower "movable" jaw -- until it closes lightly onto the paper.
- 2). Pull the paper out from the jaws without loosening the spindle. This will wipe the surface of the jaws clean and allow for greater accuracy when resetting.
- 3). Close the jaws all the way until you hear a "click" or until the jaws cannot close anymore.
- 4). Insert the spanner wrench included with the micrometer into the small slot immediately above the measurement markings on the sleeve -- the twistable handle portion -- and rotate the sleeve until the zero line lines up perfectly with the zero line on the "thimble" -- the piece above the sleeve.