Soak them in hot water and the skins will lift off easily. If you can them skins and all the skins may pull loose by themselves, but once cooked these skins are tough and not like the raw ones. You may not want them in your tomato recipes. I've never turned the jar upside down after filling them. I'm not sure what purpose it would be. I put them directly into the canner, fill it with water and process for a half hour after it begins to boil. Hope this helps.