You should use MLA referencing as soon as you start researching or writing. That way you are less likely to forget to include a citation and it is also easier than trying to add references at a later stage.
Cite This For Me is an excellent Chrome add on which is easy to use.
What exactly is a reference?
A reference is a way of indicating to the reader, in an orderly form, where information has been obtained.
A reference provides all the information needed to find the source material. References must be cited because they acknowledge the sources used, and enable the reader to consult the work and verify the data that has been presented.
References must be given whenever someone else’s work is quoted or summarized. References can come from many different sources, including books, magazines, journals, newspapers, e‐mails, Internet sites and interviews.
Internet references should include the title of the extract used as well as the web site address, the date it was accessed and, if possible, the author.
Caution should be exercised with information on web sites that do not give references or that cannot be cross‐checked against other sources. The more important a particular point is to the essay, the more the quality of its source needs to be evaluated.
So what is a citation?
A citation is a shorthand method of making a reference in the body of an essay, which is then linked to the full reference at the end of the essay.
A citation provides the reader with accurate references so that he or she can locate the source easily. How sources are cited varies with the particular documentation style that has been chosen.
Page numbers should normally be given when referencing printed material: in some styles this will be in the citation, in others in the full reference.
Once again, it is important to emphasize that there must be consistency of method when citing sources.
Appendices, footnotes and endnotes Appendices, footnotes and endnotes are not an essential section of the extended essay and examiners are not required to read them, so care should be taken to include all information of direct relevance to the analysis and argument in the main body of the essay. An essay that attempts to evade the word limit by including important material in notes or appendices risks losing marks under several criteria.
Unless considered essential, complete lists of raw data should not be included in the extended essay.
Students should not constantly refer to material presented in an appendix as this may disrupt the continuity of the essay.
For further information, consult the following links: http://www.dartmouth.edu/~sources/contents.html This site gives a complete, clearly organized summary of all the main issues involved in citing sources.
http://www.lib.msu.edu/harris23/general/citation.htm One of the best from the Michigan State University Libraries System.
Andrew Harnack and Eugene Kleppinger have published a book on citing Internet sources called on Online! The book's website has excellent advice on each style. MPA: http://www.bedfordstmartins.com/online/cite5.html#1
Citation Guides for Electronic Documents from the International Federation of Library Associations and Institutions. http://www.ifla.org/I/training/citation/citing.htm