Welcome to exante and good luck!
You can have your packs when you want. It doesn't matter. Some people have them all in the afternoon, some one in every 5 hours. It really depends on how you feel.
Listen to your body. But please, have all 3 every day.
Drink a lot. That will help you.
This is what you can drink: http://www.minimins.com/exante/197219-what-can-you-drink-exante.html
Keep strong and have great loss on your first wi! good luck!!
Keep your motivation for doing it close to the front of your mind
I started last week (Tuesday) and am really surprised how easy I've found it, although being in the house at the weekend when the kids had pizza and chips with loads of salt and vinegar on was tough to get through
I've never done a low cal diet before and was really worried about getting bad headaches but only had one for a couple of days so it's been OK