Hi.

Answer depends on version of MacWord and whether you installed the equation
editor (believe in Value Pack for Office X).  If you installed the Equation
Editor, I think you would just doubleclick, but I am not sure Equation
Editor is part of a default installation.

However, Equation Editor is a watered down version of MathType, and I am
going to quote below a message from a MathType employee, as using MathType
Lite might be simpler than dealing with Word's equation editor and updates
(as you have to re-run updates if you install anything from the Value Pack).

Also bookmark this link, as it will help you with direct access to
Mac-specific newsgroups, which are likely to be better for questions that
involve such software interactions rather that wholly internal manipulation
of Word.
<http://www.microsoft.com/mac/community/community.aspx?pid=newsgroups>

DM

Quoting Bob Mathews:
_________

Simply download MathType from the link in my
signature. This is free and full-featured for 30 days. After that
time, if you choose not to pay for it, you can still use it
indefinitely in a reduced-features "MathType Lite" mode. All
features and functionality of Equation Editor are retained, and
you can continue to display, print, and edit all Equation Editor
and MathType equations. And all of this can be done now,
regardless of the update status of Office.