Water water water! Sparkling water is good because the bubbles fill you up and it feels like a treat (weirdly)!
Make sure you have warm clothes around because you WILL get freezing after a couple of days (side effect of ketosis)
Have some well-tested distractions in place when you feel hungry, like a bubble bath, or a DVD you love (mine is SATC).
USE THIS FORUM - that's the best one. Everyone on here is awesome and so supportive. We've all experience the bad times as well as the good and we all muck in and help out when people are struggling.
In my first few weeks I used to read all the posts on here, especially from the ones who has lost gargantuan amounts of weight, for inspiration. It helped me to think that one day I WILL get there.
Good luck!