Sit or stand up straight with your hand up, fingers together and straight.
Bend the top two joints of your fingers so that the tips touch the inside of your knuckles.
Your knuckle joint should still be in line with your palm.
Next, bend your knuckles, keeping your fingers all tightly curled in.
Finally, straighten the end joint of your fingers reaching the tips of your fingers towards the heel of your hand.
Reverse the movement to return to the starting position.