Here is my special tip for you: Keep a diet journal while doing the cabbage soup diet. This might be the most important tip of all. Read here why.
You'll need it to keep track of all the facts.
For instance you'll record your starting weight and measurements in your diet book. With this you'll know at the end of your first seven days how much you have lost in terms of pounds and inches.
For me my diet book was more than just a record keeping device. In fact writing in it was a form of self-talk, made visible in ink or pencil. A motivating tool where I reaffirmed my intention to stick to the rules of the diet and cheer myself on.
There may be times during the diet, when you feel a little shaky. Times when you are tempted to eat a favorite food that's not allowed. I also felt times when I didn't feel at all positive about my possibility to lose the weight I wanted to lose.
Never mind. Write as if you believe. With positive self-talk, the strong words and phrases you use in your diet journal will take a power of their own. It's like a self-fulfilling prophecy in a very real sense.
The kind of "diet book" I'm talking about is different from a diary in which you confess also your failures and darkest fears. Just as positive writing has the power to strengthen and motivate you, negative writing can undermine and weaken your resolve.
However it can be very helpful to write about close calls - times when you felt tempted to chuck the diet and go for a high-calorie chocolate attack, but didn't, for example. The fact that you resisted proves how strong and commited you are. That's something to feel good about and give yourself credit for.