There are various ways to add references to Zotero.
Manually:: You manually enter bibligraphic information.
By Icon: If you have installed either Zotero for Firefox or Zotero Standalone along with a browser extension, an icon (a different icon for each type of source) appears in the browser toolbar. All you have to do is click on it and all information is imported.into your Zotero library.
To insert an item manually, open either the standalone or Firefox version of Zotero. Click on the New Icon button (circled below), which opens up a dropdown menu listing source types (book, book section, journal article, newspaper article, etc). A window pane opens on the right with slots for you to enter all relevant bibliographic information. The example shown here is for a book.
Click on the icon circled below. A box will open in which you type in the ISBN, DOI or PMID for the item you want to insert. The item will be added to your Zotero library.
Remember that in order to add items by icon you must have installed either Zotero for Firefox or Zotero Standalone along with a browser extension (Chrome, Safari).
When you find a journal article, a website, a newspaper article, a reference to a book (either on Amazon.com or a library catalog,), an icon (a different one for each format) appears in the right-hand corner. The icon is always to the right of the Z icon, but its appearance changes slightly depending on what type of source you're viewing and saving.
The screen below shows a record for a book in Search@CULibraries. To enter the bibliographic data for this book into Zotero, simply click the icon to the right of the Z (the icon that the blue arrow points to in the image below). Then choose "Save to Zotero using Primo". The data will automatically be imported into your Zotero library.
The screen blow shows a record from a database for a journal article. Notice the icon is not the same as for a book entry. Again, just click on it to get all the bibliographic information into Zotero.
The screen below shows yet a different icon for a website. Researchers often find it difficult to know how to cite a website. Zotero can help, but you may need to edit it according to the requirements of your professor.