Step 1. Clean the outside of the watch with a selvyt, at the same time checking to see how it should be opened.
Step 2. If the watch has a continuous bracelet, take a tool with a point and release the spring bar in the clasp to separate the bracelet into two sections.
Step 3. Using a case-opener, gently open the case and take off the back.
Step 4. Note which way the old battery was inserted.
Step 5. If applicable, unfasten the battery clamp.
Step 6. Turn the watch gently onto its side and, with the help of plastic tweezers, ease the battery out.
Step 7. If the contacts are dirty, clean them with a buff-stick.
Step 8. Referring to the operating instructions, the movement, or a cross-reference guide, ascertain the type and model of the new battery that should be used.
Step 9. Take a new battery from your stock, remove it from its package, and check that it is in good condition.
Step 10. With plastic tweezers, insert the new battery in the watch.
Step 11. If applicable, fit in the battery clamp.
Step 12. Turn the watch over and look at the hands to make sure the watch is running.
Step 13. If the watch has a gasket, check that it is in good condition and place it in position. If it is not in good condition, replace it with a new one.
Step 14. Check the cleanliness of the inner side of the caseback and clean it if necessary. Put the caseback on again and close the watch.
Step 15. If the watch has a continuous bracelet, fit the spring bar into the clasp. Set the watch and give it a final polish with a selvyt before handing it over to the customer.