Tools, Customize User Symbols
Use Customize User Symbols to change number of cells, cell size and fonts used in the User Symbols bar or to change the set of symbols displayed.
Note: The default number of cells is used when creating new User Symbol sets. To change the number of cells in the current set, choose Sets.
To change the cell size,
enter new values in the Width and Height edit fields.
To change the fonts,
choose Change to display the Font Dialog.