Magic Mouse Utilities supports left, right and middle clicks.

Left click

Left clicks are always single finger on the left side. Depending on the middle click mode.

Left clicks can also be performed with 2 or more fingers anywhere.

Right click

Right clicks are always single finger clicks on the right side.

Do not touch the mouse with any other fingers while clicking otherwise it will be a left click.

Middle click

Middle click has four modes, can be single, 2 or 3 finger clicks.

All possible clicks

 The table below illustrates all possible clicks depending on the middle click modes:

Disabled

Middle click disabled FingersLeft clickMiddle clickRight click
1 finger left half   right half
2+ fingers anywhere    

1 finger click in the middle

1 finger click in the middle FingersLeft clickMiddle clickRight click
1 finger left third middle third right third
2+ fingers anywhere    

Any 2 finger click

Any 2 finger middle click FingersLeft clickMiddle clickRight click
1 finger left half   right half
2 fingers   anywhere  

Wide 2 finger click

Wide 2 finger middle click FingersLeft clickMiddle clickRight click
1 finger left half   right helf
2 fingers   anywhere,but fingers
spread by half of the
width of the mouse
 

Any 3 finger click

Any 3 finger middle click FingersLeft clickMiddle clickRight click
1 finger left half   right half
2 fingers anywhere    
3 fingers   anywhere