The most important element of a successful insurance claim is evidence. It’s important to gather as much as you can at the scene of the accident. Take pictures or a video walkaround of the scene if you can.
If or when the police arrive at the scene of the accident, describe what happened to the police officer but do not give opinions to anybody else about the accident (who or what caused it, for example). Insurance companies may use that information against you if you make a claim.