Drink lots of water etc, they gave me a diet sheet and all I remember is avoid beetroot!
It's a build up of calcium in your bladder, they drop off and you've got to pass them through your piss hole - unbelievable pain
Feel for you pal, had them myself and you're not joking about the pain. They reckon it's the nearest a bloke will get to the pain of giving birth, had mine zapped with a lazer in the end.