Brackets and braces are added on the Layout page of the Score Settings dialog. The settings you make are specific for the current layout, i. e. you can have different brackets or braces set up for different track configurations.
Procedure
Open the Score Settings and select the Layout page.
In the track list, you can find columns for braces { and brackets [.
Click in one of the columns and drag downwards in the list to encompass the desired staves.
The column indicates graphically which staves are encompassed by the brace or bracket.
Figure: Click at the first staff for which you want a bracket or brace…
Figure: …and drag downwards in the list to enclose the desired staves.
Close the dialog.
The score is displayed with brackets or braces according to the settings you made.
You can edit brackets and braces in the dialog by dragging the ends of the indicator in the list.
To remove a bracket or brace, click its indicator in the list.
You can automatically get broken bar lines based on the brackets you have added.
If the “Show Braces in Edit Mode” option is activated in the Preferences dialog (Scores–Editing page), brackets and braces are shown in Edit Mode as well.
