I started off REALLY slow.. Like, one serving of fruit on Monday with no grains, then another serving of fruit on Tuesday (still no grains), and so forth until I was certain that the one serving of fruit wouldn't mess me up with cravings, then I added a second serving of fruit. I personally didn't add grains for the first week and a half of Phase 2, and then I dropped one serving of fruit and added one serving of grains.
Eventually I found the "happy place" with grains and fruits, but it took a while.. Just pay very very close attention to your cravings and "hunger" levels and you should be just fine