SIZING
TAPE METHOD
Place a piece of tape across the widest part of your nail and mark it. Measure it with a ruler (you can also use a measuring tape).
Example in mm (from thumb to pinky):
Left: 15, 11, 12, 11, 9
Right: 15, 10, 12, 11, 9

STANDARD SIZES
These are common sizes, but they may not be ideal for you. Whenever possible, use the tape method.
