To add a part name to all parts that automatically shows the correct instrument name:
Make sure only a single player is currently visible.
Make a text box by selecting the Text Tool and clicking on the page where you want the text to appear.
Choose the Insert Part Name command from the Text menu.
You should see the name of that player appear in the text box.
Select the part name by clicking to the left or right of it inside the text box and dragging across the name.
Make font, size, and style selections from the Text menu to set the appearance of the part name.
Finally, choose a setting other than This Page Only from the pages menu.
For example, if you want the text to appear on the first page of each part, choose First Pages. You may want to repeat this process a second time with a different Pages setting; it is common to show the part name in large letters on the first page of each part, and in smaller letters on subsequent pages.
Press the enter key on your Macintosh keyboard to stop editing the text.
