Wash the canning jars and lids in warm soapy water and rinse well (cleaning them in the dishwasher will also work). Place the empty jars into the water bath canner on the rack, and cover completely with water. Cover the pot with the lid and bring to a boil for at least 10 minutes.
Carefully remove the jars when ready to begin filling them and set them on a towel instead of directly on top of the counter (otherwise they could crack or break once they touch a cold countertop).
Return the water in the canning bath to a boil. Prepare the lids, not the rings, by placing them in a separate pot of warm heated water. Do not boil the lids because they can get damaged.
Fill the jars using the funnel, leaving 1/4-inch of headspace.
After filling the jars run a small flat spatula around the inside of the jar to remove any air bubbles. Most canning kits come with a tool for doing this. If the headspace of the ingredients changes add a little more in order to bring it up to the proper level.
Clean the rims of the jar with a damp towel and center the lid on top of the jar. Screw the rings to fingertip tight but don't overtighten them.
Place the jars into the canner making sure the water covers the tops of the jars by at least 2 inches. Bring to a boil and set the timer for 10 minutes.
Turn off heat and remove the jars from the canner (each lid will make a 'ping' sound once it seals). Let the jars sit for up to 12 hours before removing the outer ring. If any of the lids feel loose move the jar to the fridge and enjoy in the next 5 to 7 days. Otherwise, place it in your pantry to enjoy later.