Changing octave's on the piano

"change" octave could be subject to different interpretations.

1] When entering individual notes:
Enter the note then...
Raise pitch by octave: Ctrl+↑ (Mac: ⌘+↑)
Lower pitch by octave: Ctrl+↓ (Mac: ⌘+↓)

2]
Raise (or lower) a string of notes:
Enter the notes then...
Add the 8va-----¬, 15va-------¬ or whatever appropriate direction from the Lines palette.

3]
Raise or lower the notes as read on a stave:
Select a different clef (One with 8, 15 above or below it).
Now enter the notes after the clef.

4]
On the keyboard itself:
Move your hands over a bit to the left or the right.