Prepare jars, rings and lids by washing in warm sudsy water. Inspect each jar for chips and cracks.
Fill the canner half-way with water and place the canning rack in the bottom of the canner or suspend over the water.
Place a second pot of water on to boil in case more hot water is needed during processing. Keep clean jars warm by placing them in the extra pot of hot water until ready to fill.
Preheat the water while you are preparing your food. If raw-packing (140°F) or hot-packing (180°F).
Working with one jar at a time, remove a warm jar from the canner and fill it with food, leaving the appropriate headspace according to your recipe. De-bubble, wipe off rim of jar with a wet napkin and place lid on top. Screw ring on jar until "finger tight".
Load the filled jar into the canner using a jar lifter. Make sure to keep the jar upright at all times to prevent leakage between the lid and rim. Repeat with remaining jars. If using suspended rack, lower it into the water.
Add more water to the canner if necessary to cover the jars by 1 inch of water. If processing time is 30 minutes or longer, make sure the jars are covered by 2 inches of water.
Cover the canner with a lid and cook over high heat until the water reaches a vigorous boil (212°F).
Set timer for processing time called for in the recipe, adjusting for altitude if necessary. Keep the water at a boil for the entire processing time. If the water stops boiling while processing, bring it back up to a full boil and restart the time. Continue to check and add more boiling water if necessary.
Once the processing time is up, turn off the heat. Remove the lid and let the jars rest in the canner for 5 minutes to prevent syphoning.
Use a jar lifter to remove the jars and place them on a kitchen towel, on a heat-safe surface. Make sure there is 1 inch of space in between jars to allow air to circulate. Allow the jars to cool for 12-24 hours before handling.
Remove the rings and check seals. The lid should be indented and you should be able to lift the jar with the lid without in coming off. Wash jars in soapy water, label and date. Store jars without rings to prevent a "false seal".