I didn't wear a real thimble until I found one that fit! While cleaning out my deceased great-aunt's sewing supplies - I found one. It looked like a piece of junk. As I used it - the tarnish wore off and I found that I had a 24 carat gold thimble! Folks warn me that gold is soft and will wear out. Not yet - 20+ years and counting. In the winter when I'm cold, sometimes it doesn't fit quite so well. Then I just lick my finger and the extra moisture does the trick. I used to go through leather thimbles like crazy. I buy any new ones I find on the market. I have to keep the middle finger nail a bit shorter than the rest so I don't break it. But there are many cool ones on the market that let your fingernail through. As a guitarist, I have gotten used to calluses on my left hand. Perhaps you can develop a good one where you need it. There are no rules - but never stop experimenting. That's how we learn and discover new solutions to problems.