I’m adding this here as a helpful reference I want to be able to find quickly, because I don’t can stuff often enough to remember what I did from one year to the next.

Lids: You can reuse a Mason/Ball jar and the screw-on part of the lid, but you’ll need to replace the part of the lid with the gasket if you’re canning. Most places that sell canning supplies also sell replacement lids.

To sterilize the jars: I typically put a large stock pot of water on the stove and set it to boil. The jars and lids should boil for about 5 minutes. I also sterilize the canning funnel, tongs, spoon for scooping the jam, and the measuring stick I plan to use. Keep this pot boiling for later.

Transfer hot jam to the jars using a canning funnel, leaving about 1/2- to 1/4-inch space at the top. (A canning funnel has a wide enough hole to fit securely inside a standard-sized jar mouth.)

Screw the lids on just enough to keep a tight seal in place but don’t over-tighten them. You want air bubbles to be able to escape. 

Place the sealed jars into the canning pot and cover with 1-2 inches of water. Bring to a boil and let it boil for 15 minutes. Remove from the pot with canning tongs and leave at room temperature undisturbed for 12-24 hours.

The jars may pop when they fully seal. After 24 hours, check that the seal has formed by pushing down on the center of the lid. This should not move at all. If it wobbles, refrigerate the jam and enjoy within 3 months.