The easiest way to save a citation to Zotero is to use your browser extension. To save a citation from your browser, select the icon displayed near the URL bar.
This will work for articles in Library databases and anything on the internet, including websites, videos, PDFs, etc.
The icon will look different depending on the type of document you're looking at.
The icon may also be different in other browsers.
Have a book or other resource you'd like to enter manually? You can do that in Zotero, too.
Choose the Add Item button in Zotero, then select the resource type you want to enter. Fill in as much information as you have for the resource you are entering.
You can also export citations to your Zotero account using the Export button in many of the Library's databases.
After completing a search in a database, select the title of an article you want to save. Locate the Export link and select Direct Export in RIS Format (or Save to Reference Manager) to save the citation in Zotero.
This will appear to download a file to your computer. You may need to click the file download to have it added to your Zotero account.
To edit citation information, select the resource you want to edit, then the field you want to edit.