CoughDrop makes it really easy to rearrange buttons on a screen. Here's how:
Then start dragging it on the screen to see it move.
Notice you can also drag to the top of the screen for some quick helper actions.
Swapping without dragging
Not all users are able to drag and drop with high accuracy, especially on smaller boards. You can also swap buttons using the button settings window. Hit the button you want to swap to bring up the button settings window.
Save and complete
When you have finished arranging buttons, don't forget to hit "Save" to finalize your board changes.
You can hit "cancel" to undo any changes you have made to the board without saving them.