Your annotated bibliography, when submitted in hard copy, should use MLA documentation and formatting principles (though you may use single spacing in an annotated bibliography). Excluding the visual indicators for "bibliographic entry" and "annotation," it should look like this on the page, where "Howe" is your last name  and page (see image below).

Your annotation should be composed of a succinct, complete summary of the source, in addition to a basic sense of how it will be useful for your work.

In works cited pages of formal essays or presentation handouts, you need only include the bibliographic entry unless otherwise noted.