I work on the English ring sizing method eg ABC etc
Some rings are best sized before the stone/ resin goes into it therefore if your size is not the size listed in the description, contact me directly and I will make one to fit you personally. Go to your local jeweller and get them to take your sizes for the specific finger you want to wear the ring on. Keep in mind that if the ring you are looking at is much wider than the sizing rings you may be best to go up 1/2 a size. Also keep in mind that fingers tend to swell in hot weather.
It's not impossible to size tricky rings but needs to go to a jeweller with lazer welding equipment. (Meaning the heat doesn't travel around the ring). Unfortunately I don't have that equipment. I can organise it, but allow some time
Bangles are always sized across the inside diameter. Put a bangle that fits you on its side on a piece of paper and draw around the inside. Measure the diameter in mm.
If you want to order a necklace to the length you want.... put a piece of string around your neck and cut it off at the length you like , then measure that piece of string in cm.