You will need:
Pectin, I use Sure Jell For Less or No Sugar Needed Recipe, I use the less sugar recipe, Oregon Berries are naturally sweet
6 pints Strawberries
4 cups of sugar
1/2 tsp butter
Wash jars and screw bands in hot soapy water; rinse with warm water. Pour boiling water over flat lids in saucepan off the heat. Let stand in hot water until ready to use. Drain well before filling.
STEM and crush strawberries thoroughly, one layer at a time. Measure exactly 6 cups prepared fruit into 6- or 8-quart saucepot.
MIX 1/4 cup of the sugar (from the measured amount in bowl) and pectin in small bowl. Add to fruit in saucepot; mix well. Add butter to reduce foaming. Bring mixture to full rolling boil (a boil that doesn't stop bubbling when stirred) on high heat, stirring constantly. Stir in remaining 3-3/4 cups sugar. Return to full rolling boil and boil exactly 1 minute, stirring constantly. Remove from heat. Skim off any foam with metal spoon.
LADLE immediately into prepared jars, filling to within 1/8 inch of tops. Wipe jar rims and threads. Cover with 2-piece lids. Screw bands tightly, turn the jar of jam upside down and leave that way for 2 hours.
After 2 hours, you can then turn jars right side up and check for seal by pressing middle of lid with your finger, if the lid springs back, it is not sealed and you will need to refrigerate.
I keep mine in the fridge and it lasts for years.