Start by holding your hand palm-upwards and placing the mouse in the palm of your hand (see picture below). Place your thumb and small finger on either side and grip the mouse softly with these two fingers.

Then turn your palm downwards and place the mouse and the base of your palm on the table top (picture - bottom left). Your thumb and small finger should continue to lightly grip the mouse - just the fleshy part where your fingerprint is should make contact. The tip of your pointing finger (index finger) should rest lightly on the left mouse button.

Your fingers should point in the same direction as the mouse "tail" or chord (picture - bottom right)