Create an account on https://www.zotero.org/user/register. Having an online account makes it possible to synchronize your sources between the desktop application and the Zotero cloud. It also makes it possible to share groups with others.
You get unlimited storage by registering or adding your BI email to your Zotero account. Read more about our institutional subscription.
Open the Zotero desktop application after creating an account to set up syncing.
1. Choose Edit -> Preferences.
2. Choose Sync and fill in your user credentials.
3. Keep the preferences for syncing suggested by Zotero.
It is recommended to take a manual backup of your library from time to time. This should be done even if you have set up a sync.
Read more about where Zotero data is stored on different operative systems: https://www.zotero.org/support/zotero_data
You can locate your Zotero library in the following way (This example is from Windows 10):
5. Clicking the Show Data Directory will open the folder with the Zotero data on your computer.
6. Backup the library by copying the complete Zotero folder and save it on another drive than the local hard drive.
Read more about backup on Zotero's web pages: https://www.zotero.org/support/zotero_data#backing_up_your_zotero_data