My hints:
Drink lots of water
Eating until you are satisfied does not mean eat until you are full. It means eat until you are no longer hungry. Big difference to those of us emotional eaters.
I think around day 2 or 3 some-not all- people feel pretty bad, low energy, low grade headache, maybe like a cold is coming on. Just go to bed early those couple days until it passes, it will pass and then you'll have lots of energy and feel pretty good to great. It's just your body getting used to the new way of eating.
If you are a big caffeine addict, it might not be a good idea to stop cold turkey. Slowly cut down to one-2 cups a day. Don't want to have those nasty withdrawel symptoms. {I knew someone who drank a ton of coffee a day, she brought her big 32 oz thermos with her in the morning and then refilled it at lunch. <gag> She went down to 1 little dinky cup in the morning, she was not a pleasant person to be around. We were secretly planning on slipping her some "Water Joe" (caffeinated bottled water) if things didn't improve. She eventually went back to her daily fix. Yeah.}
Good luck, and have fun on the Beach!