Bracelets are sometimes tricky to measure well - particularly bangles and cuffs which cannot be laid out flat.  This tutorial for a simple bracelet measuring tool by HoneyBeads1 does a quick job of determining the inside circumference. It is best made from a plastic strip which is more durable than paper.  Clear page dividers or page holders are a couple of suggestions.

Marking the start with an arrow is good tip especially if you are using clear plastic.

A cylindrical tool like this is better for wide bracelets than the conical style measuring tools.

If you make this tool about 10 inches or so, it can also be used to determine the size needed to make bangles.  Just roll it up large enough so a hand can go through.

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Original Post by THE BEADING GEM
Jewelry Making Tips - Jewelry Business Tips