Jewelry Making Tips

What size do you usually do for bracelets and necklaces?
Basic Bracelets are 7½". We can make them larger by offering an extender.
Necklaces on the other hand are a whole other thing. It's always good to have multiple sizes if you are selling, make a variety of sizes, from 18" to 30".
Keep in mind the below tips will be helpful:-
Overall size of the piece/metal: length, width, thickness or gauge of metal?
Or how the piece wears: length of chain, how it hangs, distance/placement on the body, diameter/circumference of bracelet?
Hope the reference images help.

Necklaces Sizes and how they look?