How hard can this be:
900g (2lb) fresh or frozen berries
900g (2lb) white sugar, warmed
(use 110g/4oz less if the fruit is very sweet)
Wash, dry and sterilise the jars in the oven for 15 minutes. Put the berries into a wide, stainless-steel saucepan. Mash them a little and cook for 3–4 minutes over a medium heat until the juice begins to run, then add the warmed sugar and stir over a gentle heat until the sugar is fully dissolved.
Increase the heat, bring to the boil and cook steadily for about 5 minutes, stirring frequently (frozen berries will take 6 minutes).
Test for a set by putting about a teaspoon of jam on a cold plate and leaving it for a few minutes in a cool place. Press the jam with your index finger. If it wrinkles even slightly, it is set. Remove from the heat immediately. Skim and pour into sterilised jam jars. Cover immediately.
Keep the jam in a cool place or put on a shelf in your kitchen so you can feel great every time you look at it! Anyway, it will be so delicious it won't last long!