What is the best way to use a Micrometer or a Vernier?

Micrometer or a Vernier

Use of Micrometer 1 Verify micrometer is calibrated by testing against relevant standard or slip gauge. 2 Check anvil faces are clean. 3 Take reading from shaft, always using ratchet to take final setting. 4 Take reading. Beware of ‘Turn of the Mike’ error. If in doubt as to readings obtained or required then ask. Use of Vernier - 49 / 50 type 1 Check close faces are clean. 2 Take measurement. 3 Take reading by adding vernier Scaled reading to nearest 1/20” Use of Vernier - Digital type 1 Switch on, Clean faces, Close together, then reset Zero. 2 Take reading, ensure correct scale is selected - MM / Inch. 3 Following reading close faces & re-check reading is zero.