Roughly peel the cucumber, leaving alternate strips of dark green skin. Slice it to the thickness of about 2mm.
Throw the pieces in a bowl and sprinkle with the salt. Leave for 30 minutes until most of the juice has been extracted.
Meanwhile, make the brine. Put all the remaining ingredients, plus extra spices and herbs if you wish, in a saucepan and bring to the boil. Take it off the heat and leave it to cool completely.
Sterilise a glass jar by washing it and the lid in hot soapy water. Put it in a saucepan, cover with cold water and bring to the boil. Leave it to boil away for 10 minutes then drain the jar and lid on a clean tea towel to air dry.
Once the jar is cool, drain your cucumber slices. Fill the jar with the cucumber and top up with the cold pickling liquor. Cover with the lid and leave in the fridge for at least 3 hours until serving.