You don't. You have to do this manually or with a macro.

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Suzanne S. Barnhill
Microsoft MVP (Word)
Words into Type
Fairhope, Alabama USA
Word MVP FAQ site: http://word.mvps.org
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> > How do I customize endnotes to enclose the end note
> > numbers with brackets? Thanks in advance.
> You don't. You have to do this manually or with a macro.
I would stay with the default. The custom with the brackets probably
originated with typewriters, which didn't have proper superscripts.
Word allows you some exotic numbering formats, especially if you use a
macro:
ActiveDocument.Endnotes.NumberStyle=5 ' 1., 2., 3., ...
ActiveDocument.Endnotes.NumberStyle=18 ' enclosed numbers (up to 20)
ActiveDocument.Endnotes.NumberStyle=22 ' 01, 02, 03, ...
ActiveDocument.Endnotes.NumberStyle=57 ' -1-, -2-, -3-, ...
But no brackets :-(
And putting brackets in as text, they are hard to maintain even if you use
macros to do it.
Regards,
Klaus