I'm sorry you're having a hard time with them. They are a pain for sure. Try using the search function on here and just type in bottlecap, you should get enough reading for days.
I tried using liquid resin and gave up, it was a pain, so I use some PU drops I bought from a member here, they're wonderful!
I could never get my bottle caps to dry completely, after letting them sit for a day, and then baking them a little bit, weeks later they are still sticky on top. I'm just going to glue some magents on the back and use them here at home.