For jam:
Wash jars thoroughly, rinse in very hot water and invert them on a rack to drain.

Place jars upright in a slow oven 150C for 30 minutes.

Use the jars straight out of the ovenminis
For storage:
To sterilise a storage jar, wash thoroughly, rinse with boiling water and place in a warm oven until completely dry.

Do not dry with a tea towel.