Tools|Customize|Toolbars Tab
Maybe create a new custom toolbar??
then click on the Commands tab
Then scroll down the category list. At the bottom, you'll see a category named
Macros.
select that.
Drag that custom button from the Commands (right hand side) box to the new
toolbar.
Right click on it and choose assign macro.
Point at your macro.
Notice all the other stuff you can modify after you've right clicked on
it--including change button image.
Now whenever you click on that icon, excel will find that macro (even open up
the workbook if it has to) and run it.
But I like a method that actually creates an additional option on the menubar
each time the workbook is opened--then cleans up after itself when you close
that workbook.
John Walkenbach has a very nice program that actually adds some items to the
worksheet menubar--it looks very neat and is easy to update. It's his MenuMaker
program:
http://j-walk.com/ss/excel/tips/tip53.htm
(It's especially useful when your list of macros grows.)