I do not believe there is a toe that is specifically singled out to wear a toe ring on. However I prefer to wear a toe ring on either my little toe or the next one to it. Wearing it barefoot or with sandals is appropriate.
Toe rings can be work any way you want to do so that is comfortable for you. Most comonly toe rings are worn with sandals or open-toed shoes, and it is also common to wear them inside shoes which will be removed at the door.
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I am a man of 65, and I wear my toe ring the big toe of my right foot, I get a few looks once in a while, but I like how it looks ans fells add a comment