How do I edit the name of a stave?

If you would like to rename your stave, press "ctrl+1" at first.
Double-click on the name of the stave.
Your default score's stave names are usually "Track 1, 2, 3,...".
A new window, "Text Properties", opens.
Select the tab "Appearance".
Change the track's name and style according to your tastes.
Confirm your choice by clicking on "apply".