My signature 'Wave' cuff in beautiful rose gold fill or sterling silver is a lovely everyday piece with great movement.  The Rose Gold also is very resistant to tarnish while having the look of copper.  A classic treat for yourself or others that will be worn for decades.
 
Order the closest to your size as possible by measuring a cuff you already own.  Metals 'work harden' with repeated movement and will eventually crack so the right fit from the start means it'll last a lifetime or more.
 
I would say these all turned out to be medium or larger.  Feel free to contact me with your measurements if you'd like a second opinion as to whether one or more of these will work for you.  I can bend them to more oval or rounder if needed...everyone's wrists are different.  There are only the four pictured that are available.