Exercise is the most effective way to reduce insulin levels. Try doing 3 (or more) brisk 10-15 min walk/run a day as opposed to one long stretch. this isn't always possible, so ANY exercise is good. It makes your cells more receptive to the insulin so it gets used up quicker. Even a quick 2-5 min with a skipping rope before and after each meal helps.
Start by reducing carbs (bread, pasta, rice, noodles) and increasing your proteins. Try to have protein at each meal (egg, meat, fish, poultry, beans, legumes, tofu, nuts - especially raw almonds).
Replace carbs with low GI options, (basmati rice, wholegrain bread, quinoa instead of rice - it's very high in protein and vit b which helps digest carbs)
Increase salad with meals. try to replace part of the carbs with salad until you are eating almost nil refined carbs ( go slow so your body adjusts).
Increase fibre. Add Benefibre to soft food, drinks (coffee,tea, juice). Have metamucil/fybogel with two glasses of water 3 times a day before each meal. This will reduce the amount you eat as well as slow the absorption of sugar in your diet.
Eat a handful of raw almonds for morning and afternoon tea. This will keep you fuller and help with sugar metabolism as well as cholesterol levels ( which will eventually rise due to increased insulin).
Eat salads with tuna/chicken/cheese instead of sandwiches for lunch.
Increase your water intake.
Read up on low GI diet so you know which foods are better options for you. Think about everything before you put it in your mouth. Is it low GI? Is it good for me? Do I need to eat anymore or am I full?
Don't stress too much stress will increase your insulin levels! Try meditation/yoga/ long warm baths - whatever it takes to relax.
And yes - don't worry about the numbers from the lab - 500mg 3 times a day of metformin is sure to help if you are disciplined with your diet and exercise.
Good luck hun. You can beat it. I did.