Ensure everyone's well-being and call the police to the scene. Their report will be vital in the future. Document the accident as much as possible—take photos of the scene, the vehicles involved, and any injuries. Even if you feel fine, it's wise to have a medical examination, as some injuries manifest later. Notify your insurance company about the incident promptly. They can guide you on filing an uninsured motorist claim, if applicable. Also, consider consulting a car accident attorney.