Gauging and saltwater disinfectant?

I gauged my ear to a 0 it got infected I put polysporin on it and it's going down and virtually gone. I went swimming in a lake And my friend let me use this saltwater disinfectant she got and it's going down and looking even better. I was wondering what the 'recipe' or how to make the saltwater solution at home. I have seasalt and disstilled water. What are the ratios?