Eye-liner, according to my rulebook, should be grey, or green or brown and applied relatively heavily on the upper lid, thickening towards the outer corner. It should be applied sparingly to the lower lid, from centre to outer corner. Followed by a smattering of smudging.
The Middleton sisters (both do exactly the same routine) have torn up my rulebook. Their undereye kohl seems heavier than their upper lid liner. And it's always black. And it's corner to corner. And it works!
And now everyone else is doing it, and I'm looking into newly defined eyes that shoot straight back at me, sparkling in a way that leaves mine feeling decidedly underdressed.
I shall be experimenting with king kohl forthwith. Reminding myself, like all those wedding makeup artists do, that 'it might seem heavy to you now darling, in the mirror, but it won't from a distance'.
Doubtless that's what Kate says to herself when she leans into the mirror, stretches that lower lid and underscores with purpose. I'm going away to practise.