You may need to edit some of your citation for misspellings, capitalization, faulty HTML or other errors. You may want to add information to reference. You may simply want to see how the reference looks in your bibliography.
Open your EndNote library.
Select a reference and double click on it.
An unformatted summary may appear.
Look to the bottom and you will see the current style and a small arrow.
Click on the arrow and you will see the reference in the selected style.
Click on Edit and you will see a list of fields.
Fill in the information you want in the appropriate field(s).
Save.
This is the arrow (to the right of the reference at the bottom). Click on it to see the reference (Summary) in the selected style.