When the band is connected to the phone, you can download new band displays through the Mi Fitness APP.
Go to the Mi Fitness APP >> [Device] >> [Manage band displays]. You can use it after downloading and importing.
The way of how to delete a band display:
Enter the band interface >> [Settings] >> [Band displays] >> swipe up and down the page to select the band display to be deleted >> tap [Delete] at the upper of the interface.
Go to the Mi Fitness APP >> [Device] >> [Manage band displays] >> [My band displays] >> tap on the corresponding band display >> tap on [Delete].
Note:
The default band display does not support deletion (factory restore requires restoring the preset band display, so it cannot be deleted here).