Log in to your ownCloud account with the Administrator details via a web browser
Make sure that the Mozilla Sync app is installed and enabled.
Logout and login with your normal ownCloud Account via a web browser.
Choose Personal (under your login name on the right hand side of the screen)
Make sure that you have a valid email address and then scroll down the page to the Mozilla Sync section and the details you need to use will be displayed :
|Password||Use your ownCloud account password|
Mozilla Sync is set up, additional devices can be added via Mozilla’s device pairing service or manually.
Next login into Mozilla Firefox on your desktop
Choose Tools > and Sync or in the browser adress bar type in about:home and choose the Sync icon disayed at the bottom of the page.
Enter the details as described in your ownCloud account (example above) and then click next when you have finished.
Your desktop Firefox should now sync its data to your ownCloud account.
To add a device, i.e Firefox running on Android mobile phone you can follow the instructions (From Part 2) at the Mozilla site here https://support.mozilla.org/en-US/kb/how-do-i-set-up-firefox-sync