Make sure jar rims are clean. (If they're not, jars will not seal correctly). While jars are still hot, place lids on jars, and screw rings on tightly. Jars will seal as they cool. Place the jars on the counter and listen for them to "ping" as they seal. If you miss the "ping", wait until they are completely cool and press on the top of the lid. If it doesn't move at all, it's sealed.