Jasper, I am quite new to this but the first two weeks you do the kick start and you simply choose a breakfast, lunch and dinner from the choices in the book and have a fruit power snack mid morning and mid afternoon, no alcohol for the first two weeks but after that its fine to as there is a alcohol allowance which can be saved up for the weekend for example.
Cos the meals have already but suggested (you can change using the low GI foods and using the same number of calories) its quite easy and the recipes I have found to be very tasty and I have found a new love for prawns.
After the 2 wks kickstart you then go onto the number of calories for your height/weight worked out by RC consultant, you then eat food throughout the day following the guidelines such as nothing over 5% fat per 100g (except for 1 100 cal treat per day) and low-medium GI foods which are listed in the book. Also recommended to exercise to keep your matabolism going etc. and I can certainly recommend this as I worked out for the 5/6 days a week 20-30mins in the morning and losts around 8 inches in the first two weeks! I can now do up some trousers I once couldn't .....and I am not one for exercise too so thats a double shock.
I too struggle with sticking to diets have had one of those "switch off" moments last week but back on track now. When followed properly the plan doesn't leave you hungry as the low GI foods leave you fuller for longer and are much healthier for you.
All I can say is give it a try the classes include an exercise group too which is much better value for money I think, so you are paying for weigh and exercise not just to get on them scales. Its educational in food nutrition and I have already started to make lifestyle changes here and there...
Good Luck!
.............gosh that was a long one .... sorry I can waffle sometimes hope you don't mind...