Either I suppose. In the book he calls for between 6 - 12 glasses a day, I have found I do well with 10 - 12 and if feel I need the last 1 or 2 glasses it is usually after my cardio workout. Or after that If you find you need more energy you can add more syrup, or take a spoonful of black strap molasses (which I have not tried and know nothing about).
What has worked for me is to drink the lemonade as needed during the day and also extra water just to keep my stomach off empty, saving the last couple of glasses for 7 or 8 at night. Then just water and tea after that.
The first couple of days will really be a personal experiment for you. Your body will let you know how much you need, just put enough liquid into your body to compensate for what you will sweat out.