"Eliminate simple sugars and refined carbohydrates, making sure the bulk of your diet comes from complex carbohydrates (whole grains, organic vegetables and berries), non-hormonally treated protein sources, alpha lipoic acid, conjugated linoleic acid, B vitamins, and magnesium."

She also has some handy guidelines in terms of supplements you might want to look into taking. Good luck!
References :
http://www.thefertilesoul.com/Treatment/Diet/Supplements/pcos.php

Diet For PCOS
Experts now consider that the best type of eating plan to improve symptoms associated with PCOS and insulin insensitivity, is a low-GI diet, based on foods with a lower ranking on the glycemic index. This is because eating lower-GI meals and snacks helps to eliminate "sugar-spikes" – the sudden rises in blood-glucose due to consumption of high-GI carbs – and so reduces insulin response from the pancreas. By maintaining stable blood-glucose levels, a low-GI diet also helps to reduce the general level of insulin circulating in the bloodstream and should lead to a gradual improvement in PCOS and insulin sensitivity symptoms.

What Exactly is the Glycemic Index (GI)
The glycemic index (GI) is a new system for classifying carb foods, according to how fast they raise our blood-sugar levels. It replaces the old distinction between "simple" and "complex" carbs. The higher the GI value of a food, the faster the rise in blood glucose. The glycemic index separates foods into three general categories:

High GI Carb Foods (GI value 70+)
These carbohydrates cause a rapid rise in blood-glucose levels

Medium GI Carb Foods (GI value 55-69)
These carbohydrates cause a medium rise in blood-glucose

Low GI Carb Foods (GI value 54 or less)
These carbohydrates cause a slower rise in blood-sugar
References :
http://www.annecollins.com/pcos-diet.htm