OK, I am the grand daddy of cramp. The cramp master. Ninja cramp man. Damn, I have had cramp so much I could write the book on pain. While riding, in car on way home, in bed, much to the annoyance of mrs gump.
However, I put this down to 3 things, follow this advice and cramp will not return!
1) Get fitter. One main cause is pushing yourself much more than normal, muscles say no!
2) However, you can overcome 1) quite a lot by hydrating. Drink shit loads. All the time. DO NOT get thirsty. Do not care about Jonno taking one bottle for a day. Bollox, take a camel back and refill if needed. Drink what you need to, and dont care if you then end up pissing every 20 mins.
3) High 5 zero. Its magic. Half or one tab in a bottle works wonders.
There it is, do all three and you will not cramp any more. For what its worth, I have spent ages playing with warm ups/cool downs etc, but tbh, aside from a quick 2 mins stretching in the car park after a ride, its all of no real use (IMO!!)
Good luck!
Andy - ex-cramp master