Jars sold usually have good instructions as well as master canners in your area. Make sure the lip of the jar is clean with no spillage. Another tip I learned the hard way is only the Ball grey rubber lids are used without deterioration. if your recipe has oil in it, i.e. marinara or salsa etc. I have to hunt for these lids west of the Mississippi. I have found only one store in the nearby area that sells them.