Howdy Uinsin,
To change any single clef symbol, you can double-click on it and then use the arrow buttons to change it to the clef symbol you want.
To change an entire staff's worth of clef symbols to a single one (eg. all bass clef), you can
- click on any clef symbol in the score to bring up the Clef palette and menu (in the top menu bar)
- In the Clef menu, click on the last item "Set clef in a range of measures"
- Select the staff you want to set the clef in, select the clef you want, and click Ok (the default range of measures is the entire song.)
The clef will now be set for all measures in that staff.
You can find out more about setting clefs in Help/Users Guide, and use the Index to look up "clef".
ttfn,
Sherry