PCOS Diet with Pregnancy?

I was recently diagnosed after 4 years of unsucssesfully concieving, with PCOS. After a regimen of metformin and clomid i sucessfully achieved pregnancy. My Doctor tells me even though i dont yet have gestational diabetes he wants me to follow a diet plan for it due to Insulin resistance with the pcos. My first baby (before i got PCOS) was large at 9.1lbs and a very traumatizing experience. My Doctor tells me this may happen again with a large baby if im not careful due to the insulin problem. Can anyone suggest a good diet plan who may have gone through the same thing i have? I would like to have as close to a "Normal" weight baby as i can and be healthy. Please if you have any information on a good diet to follow while pregnant with insulin resistance/pcos let me know. Thanks in advance