If the Accents section of the Part box isn’t visible, click the Accents button in the Part box.
Do one of the following:
To add a symbol to a single note: Drag a symbol from the Part box onto the note.
To freely place a symbol: Press and hold Option, then drag the symbol from the part box to the position you want to place it.
To add symbols to multiple notes: Select multiple notes, then drag a symbol from the Part box onto the selected notes.
To add symbols to one or more notes: Select a symbol in the Part box, then click one or more notes using the Pencil tool.