Double click on the Symbol button in the object type palette in the Copyist Tools window to open the symbol palettes. Click on the Clefs palette. The Clefs palette will open, showing you all of Copyist's clefs.
Select the kind of clef you want by clicking on it. The clef you choose appears on the Symbol button.
Choose the pencil tool from the Toolbar. Now enter the clef symbol on your page. Do this by clicking and holding down the left mouse button. The clef will appear at the mouse cursor. As you continue to hold down left mouse button, you can move the mouse and the clef will follow, until you have positioned the clef where you want it on the page. When the clef is positioned where you want it, lift the left mouse button and the clef will be placed onto the page.
If you want to undo the clef entry operation, select Undo from the Edit menu.
You can move or edit the clef after you have entered it, by double clicking on the clef and selecting one of the edit operations from the edit menu that appears.