To edit a note first select it.
A selected note
Drag any rotate manipulator 
to rotate the note.
Drag any scale manipulator
to re-size the note.
Drag the note to move it.
Note Properties Dialog
You can also edit the parameters of the note using its properties panel as shown below. To view the properties panel first select it.Then right-click on it and then select Properties Panel from the context menu that opens.
Note Properties Dialog
X
The X coordinate of the center of the note.
Y
The Y coordinate of the center of the note
Width
The width of the note.
Height
The height of the note
Roundness
Drag the slider to change the roundness of the notes corners.
Layer
Use this drop-down to set the layer for the note.