Since EndNote creates a copy of the paper during the formatting process, you can always reformat the original document, if necessary, to create a new document with the changes that you need.
Reformatting with Different Styles
The appearance of both the in-text citations and the bibliography in the formatted paper is determined by the selected style. If you need to create a copy of your paper in a different style than what you did originally:
From the Tools menu in EndNote, select Format Paper > Format Paper. Open the original unformatted copy of your paper (the one with the EndNote citations surrounded by curly braces or brackets).
On the Citations window, select a new output style from the Output Style drop-down list. You can select one of the "favorite" styles currently in the list or choose Select Another Style to pick a style from the + styles shipped with EndNote.
If the Citations window shows that all the citations in the paper are correctly matched, click the Format button.
EndNote will prompt you to name and save the new formatted copy of the paper. Notice that the style name is included as part of the new paper’s name. That will help you distinguish between various copies of one paper (perhaps formatted to be submitted to different journals).
When you open the new formatted copy of your paper, you should see that your citations and bibliography use the new bibliographic format.
Important: When you need to make changes in your paper, remember to work only with the unformatted copy of the paper (the one with the bracketed temporary citations), rather than the formatted copy that EndNote created.
Adding New Citations to Formatted Papers
If you have already formatted your paper, and you see that it needs to be edited by either adding or removing citations, you must return to the original, unformatted copy of the document (the one with EndNote’s "temporary citations"). Open that document in your word processor. Add, modify or delete citations as necessary, and then save the paper as RTF. You may now format the paper (as described above) to create an updated copy of it.