If you have never been in this situation before, you should contact a personal injury attorney in your area to assist you. They can help you walk through these steps with you. You don't want the insurance company to take advantage of you.
I agree with my colleagues, you should definitely speak with a PI attorney. Uninsured motorist claims are pretty adversarial and your insurance company will try to settle for as lowest amount of money as possible. It's best to meet with an attorney who could review your case and put forth a strategy to maximize a fair award for you.