1. Get additional microSD cards, see which microSD cards are supported.
2. Plug the new microSD card into your BitBox02.
3. Launch BitBoxApp, connect your BitBox02 & unlock it.
4. Go to "Manage Device" > "Manage Backups".
5. You will see that the new microSD card does not contain any backups so far.
6. Click the "Create Backup" button to save a wallet backup onto the new microSD card.
When done, store your wallet backup microSD card in a safe location.