While doing your research, be meticulous about documenting every source that you use. If you leave it until later, you will lose it. If the source you are using is a book, then note the author, title, publisher, place and date of publication, and the relevant page numbers. If it's a journal or periodical, you need to note the author, title of article, title of journal, pages numbers of the article, page numbers of your source, volume, edition, and date.
Write a book citation with this layout and style:
Fisher, David James. Romain Rolland and the Politics of Intellectual Engagement. Berkeley: University of California Press, 1988.
Note the required elements: author's surname, author's first name, period. Double space, followed by the title of the book, underlined, period. Double space, followed by the place of publication, colon, publisher, comma, year of publication, period. The first line of each citation begins at the left margin and each subsequent line in that citation is indented one tab space.
Write a periodical citation with this layout and style:
Ong, Walter J. 'World as View and World as Event,' American Anthropologist Vol. 71, No. 4 (August 1969), p. 634-47.
Note the elements for a periodical citation: author's surname, author's first name, period. Double space, followed by the title of article in quotations, comma, followed by the title of the periodical, underlined, followed by volume number, issue number, date in parentheses, and beginning and ending pages of the article.
If a citation runs to multiple lines, single space them. Double space between citations. If your sources fall easily into different groups (i.e. sources about economics and sources about geography), you can make those categories the basis for two separate sections. Check the regulations and preferences of your discipline.
Proofread your citations page several times. Chances are you'll catch mistakes each time.