Basically it is ' no snacks, no sweets, no seconds, except on days beginning with S' the guy who invented it had a good website explaining it all. I find weekends hard, as in I tend to eat too many sweets etc but he says it gets easier.
It should work for me because I reckon I was eating 1000 cals of junk daily either binging or telling myself 'I'll start tomorrow' so I'm probably eating slightly bigger meals, but it feels satisfying not to pick, or have seconds etc. It's early days, but I'm enjoying it so far.