To create your free account go to https://www.zotero.org/ and click the "Download Now" button. When creating your account you can use whatever email address you would like, it is not necessary to use your FDU email address.
Once you've installed the Standalone App a page will open in your default browser letting you know Zotero successfully installed. It will also ask you if you would like to install the Web Plugin for the same browser.
Further down the page you will be given the opportunity to register with Zotero and create an account. This is important if you would like to use Zotero's web based client.
If you forgot to register or accidentally closed this window before doing so, you can still register at https://www.zotero.org/user/register/.
Once you create an account you will need to enter your information in to the Zotero Standalone App to sync your account. Click on Tools >> Preferences >> SYNC >> Enter your username and password and keep the Sync options checked.
Depending on your security settings, Firefox will ask you to confirm the plugin installation. Click Allow.
Firefox will once again prompt you to install the plugin. Click Install.
The first time you try to use the plugin it will ask you sync with your Zotero Standalone App. Click Yes.
The plugin will appear as a Z and Paper icon in your browser's tool bar. The Z will open your Standalone App while the paper icon will import citations in to your Standalone App.