Saving citations to Zotero is easy. Once everything is installed, you'll have a Zotero button in your browser.
Whatever page you're on, Zotero will automatically know what type of page it is. Here's an example of a webpage:
Zotero does the same with the Library's database. It automatically knows it's an article:
When you click the Zotero button, you'll get a quick pop-up that will indicate that the extension is saving the page to your Zotero library. A great bonus for articles is that Zotero will automatically save the citation information but also downloads the pdf for you.
Once you've save the article, it's immediately waiting in your library.