Once Zotero is installed:
To create a new collection, right-click on My Library or click on the New Collection button (above the left pane)
A new collection is a folder into which items relating to a specific project or topic can be placed. The same item can belong to many collections at one time.
To change the citation style in Zotero, go to:
View > Citation Style .
You can click on More Styles if you do not see your preferred style in this list.
Do note that if you have downloaded a free version of Zotero, not all styles come pre-installed. Hence, click on the tab Get More Styles to search for your preferred style in Zotero's online database if you need to.
Zotero allows you to attach a PDF to any references added in the library.
To attach PDF to any entries: