1. Open the settings application of the mobile phone, which can usually be found in the application list or on the home screen.
2. In the settings application, find and click "wallpaper" or similar options.
3. On the wallpaper setting page, select "Automatically change wallpaper" or similar options.
4. On the automatic wallpaper replacement page, you can choose different wallpaper sources, such as photo albums and Xiaomi theme stores.
5. According to personal preference, choose the frequency of wallpaper replacement, such as daily and weekly.
6. After confirming the settings, the wallpaper will be automatically changed according to the set frequency.