The first week is the worst. Once you get into ketosis, it's smooth sailing. You will no longer be hungry and you won't have any more cravings.
I am sure your coach will tell you, but during your first week, it is ok to go up to 5 packets a day (only 1 can be restricted, though).
You can also have 2 eggs whites a day (free), so take advantage of them.
If you get a headache, try licking some of the salt off of your hand. Or eat a pickle or 2. This will also satifsy a crunchy/salty craving.
Take advantage of the unlimited lettuce. Steam your veggies and save your olive oil allotment for making a salad dressing to use on the lettuce. This way at lunch and dinner you can have a "salad" and your veggies. This will help fill you up. I use the Good Seasons dressing. It is the one you buy the carafe for. The envelopes are only spices, and I make it with water, apple cider vinegar and olive oil.
Drink tons of water.
Also, I know they say no gum, but if it means that a piece of gum will save you from eating off plan, I chose the gum every time.
Again, once you make it through the first week, it will get easier. And once you start seeing the results, well that will be motivation enough to stick with it!