Each year the apples take longer to ripen than you remembered.
The apples are so lovely on the tree. Why pick them at all? 
Some people like their jelly very sweet. I add the juice of a lemon
A little dark fruit in the early stages (a few blackberries?) may improve the colour.
The juice must be carefully strained. You can’t crush it or rush it.
When you add sugar and bring to the boil, you need to skim off the froth.
You’re aiming for the perfect set.
There is a ritual for testing the set. (Modern technology is not required.)
Each batch of jelly should have a title, with labels on the jar.
The jars of jelly should be stored in a dark, cool cupboard.
You can enjoy it all yourself, or you can share.
Other people’s jelly is good but rarely as enjoyable as your own.
You are only as good a jelly-maker as your last jelly.
Notes:
1. Crab apple blossom can cross-pollinate most other apple trees.
2. The BBC Food recipe works well.