Step 1: Clean the watch. Although the watch is small in size, its internal structure is very complicated and precise. A little dust or clothing fiber will affect the watch's running time. Therefore, before replacing the battery, the bottom cover of the watch should be cleaned like surgery, and the gap between the bottom cover and the bottom cover should be cleaned with a vacuum cleaner when opening the bottom cover. Step 2: Open the watch bottom cover. Professional tools should be used, and special brands should use brand-specific tools. Avoid the deformation of the bottom cover to affect the tightness of the watch. The back cover of most watches is spiral. How to open the back cover of a watch can only be opened with a watch opener or a watch opener. When using the rice opener, you can twist the back cover slightly in the tightening direction and then in the loosening direction. If the back cover is found to be too tight, you can drop lubricating oil around the back cover, and the back cover of the watch can be opened in a while. For the push-type watch back cover, how to open it? When pressing, the thumb of both hands should be pressed properly and the force should be uniform. Step 3: Measure the battery voltage under replacement. (Many watches are still not easy to use after replacing the battery because the previous battery power itself is normal, and the watch fault still exists after replacing the battery. If the watch is left for a period of time, the movement should be tested even if the measuring battery is exhausted. Step 4: Replace the original battery. Try to choose the original brand or origin battery. Wear a finger sleeve when replacing the battery to avoid the sweat on your fingers polluting and corroding the movement and never taking it out. Step 5: Check the waterproof fittings. Waterproof accessories of watches are generally made of rubber or plastic, and there will be an aging period. After aging, waterproof accessories will lose their waterproof performance. If the waterproof fittings are aging, they must be replaced, otherwise the watch will get water or get wet, which will make the movement oxidized and rusted, resulting in irreparable faults. (Waterproof accessories need to be inspected once a year according to the requirements of the watch instruction manual). Step 6: Test waterproofing. To ensure the stability of the movement, we must first ensure the protection of the watch case to the movement, and the most important thing is the waterproof performance. Step 7: issue a warranty. Due to the different states of the movement, there is no guarantee that any movement can reach the longest battery life after battery replacement. At the same time, customers are advised to maintain watches with poor movement to restore the best working condition.