Zotero has two ways to quickly create fully formatted bibliographies with citations in your library.
See more on creating bibliographies from Zotero.
Zotero comes with the most common bibliographic styles, but many more are available to download.
To install a Zotero style:
The new style will appear in Zotero's style lists.
Word processor plugins, including those for Google Docs, Microsoft Word, and OpenOffice/NeoOffice, create dynamic bibliographies: insert a new in-text citation in your manuscript, and the bibliography will be automatically updated to include the cited item. Correct the title of an item in your Zotero library and with a click of a button the change will be incorporated in your texts.
Video by the Roy Rosenzweig Center for History and New Media.
Video by Daniel de Byl
Do you use a word processer that doesn't have a plugin? Do you know the date of the your citation off the top of your head? Is the plugin slowing you down? Zotero's RTF Scan is the answer for you. Put your work in a RTF document, write the citations yourself, and tell Zotero where you want the bibliography and have Zotero do the rest of the work for you.
More on RTF Scan from Zotero.