OK - I have dug out my very tattered Penguin Cookery book, and this is the recipe I use.
8oz self raising flour (I have never used strong flour, and have never had any problems).
1tsp salt
1-2oz butter
0.25 pint milk.
Sift the flour and salt together and rub in the butter. Add the liquid, mixing with a knife - you can use sour milk or sour cream instead of the milk. Pat the mixture out and cut the scones. Egg wash.
Bake for 8-10 minutes in a hot oven - gas mark 7-8, the book says.
I make fruit scones by adding sugar instead of salt, and either sultanas or glace cherries, and when I egg wash the scones, I sprinkle on some brown sugar, to give them a nice crunchy top.
For cheese scones, the recipe says to add 2oz of grated cheese - but like @KatherineJaneway, I add more - lots more! I use a really strong cheddar, and add at least 6oz of grated cheese - and I put a heaped teaspoon of wholegrain mustard in the milk.
To be honest, I put in too much cheese - the scones don't stay scone shaped - they slump because the amount of cheese I use ruins the structural integrity of the scone - but they taste utterly delicious, so I don't care!