Hi @Siri welcome to our awesome Forum 
Creating your dragon on a ring that you wear daily is a great idea. The “one inch” is not a rule set in stone, it was just a recommendation from Dream. Many other members have placed their dragons on items a lot smaller and still had success. Your ring may not be one inch wide but I am pretty sure the circumference of the ring will be close to an inch? unless you have really tiny fingers 
(Wrap a string around the finger you will be wearing the ring on, then lay it flat and measure it)