Allow enough room to accommodate your knuckle.
Bear in mind, different fingers on the same and the opposite hand may have different sizes. Therefore, measure the specific finger on which you are planning to wear the ring.
Measure your finger at the end of the day when your finger is likely to be largest.
BRACELET SIZING
Bracelet sizes are listed as circumference in inches or cm. To measure your wrist use a piece of string to desired fit and lay the string back out on a ruler to get your measurement in inches.