The plate test
When you start cooking put three or four saucers into the freezer. Then when you think your preserve is ready, turn off the heat and put a teaspoon of the preserve on a chilled saucer and put back into the freezer for 1 minute. If when you push your finger through the preserve it crinkles then it ready. If you think it needs longer put the heat back on for another 5 minutes and then re-test.
The flake test
Dip a wooden spoon into your preserve then lift out the spoon and twirl it around a couple of times. Hold the spoon sideways over the pan and if the drips run together to form a flake then setting point has been reached. If you have not tried this test before, use the plate test first and then try this one to make sure you know what to look for.
The temperature test
Put a jam thermometer into the pan when it has reached rolling boil. Once it reads 104.5°C setting point has been reached.
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