Really. Tell them to have Microsoft or any number of other programs format those citations for them.
Although you may not guess it, interviews with SNL students indicate that they spend an inordinate amount of time and energy worrying about how to format their citations, time and energy that would be much better spent on developing and organizing their ideas; researching, evaluating, and synthesizing sources; and drawing conclusions.
Similarly, teachers spend an inordinate amount of time teaching, correcting, and being frustrated about students' formatting of citations. Time that would be better spent giving students feedback that challenges them to develop, support and organize their ideas.
As the videos below indicate, students can use Microsoft Word to format their citations and bibliography. The nice thing about this tool is that when students enter the information for a source once, they do not have to enter it again when they are working on a new paper. Similarly, Zotero is a free web-based tool. To learn more about it, see http://libguides.depaul.edu/zotero
To share this information with your students, send them to http://snl.depaul.edu/writing/Writing%20Help.html#helpsources