1. Keep your vehicle in good running order. Routine maintenance and replacement of worn parts in a timely manner will significantly decrease the possibility of breakdown when you are least prepared.
2. Consider having a cellular phone installed in your vehicle. Often this is the quickest and safest means of alerting the police and emergency services that you are in need of assistance.
3. If your travel plans include overnight or long-distance driving, make sure you leave an itinerary of your trip with friends or family to let them know where you will be staying-including phone numbers of overnight lodgings.
4. Plan road trips carefully. Consider weather and driving conditions in relation to the condition of your automobile. Carry maps and familiarise yourself with the route you will travel before you leave.
5. Have an emergency kit, including a working flashlight and jump cables, in the car at all times. Consider a first aid kit and emergency blanket as well.
6. Often a "Send Help" sign for your windscreen can be a valuable item if you are not able to get your vehicle going.
7. If your car develops problems, find a telephone. On motorways follow the marker arrows to the closest phone. They are never placed more than a mile apart, on opposite sides of the motorway. NEVER cross the carriageway to use a phone.
8. While on the hard shoulder or telephoning, keep a sharp look-out and don’t accept lifts from strangers - wait for the police or breakdown service. Don’t wait in the car - there is a high risk of an accident. Wait on the embankment nearby with the front passenger door open. If someone approaches you or you feel threatened, lock yourself in the car and speak to them through a small gap in the window.
9. If someone tries to flag you down, drive on until you come to a service station, or somewhere busy, and call the police. Do not pick up hitchhikers.
10. Keep doors locked when driving and keep bags, car phones or valuables out of sight. If you have the window open, only wind it down a little. Don’t wind it down far enough to allow someone to reach in while you are stopped at traffic.
11. If you think you are being followed, try to alert others by flashing your lights and sounding your horn. Make as much noise as possible. If you can keep driving until you come to a busy place.
12. After dark, park in a well-lit, busy place. Look around before you get out. If you’re parking in daylight, but coming back for your car at night, think about how things will look in the dark.
13. Have your key ready when you go back to your car. Make sure there is no one in the car.
14. Don’t drive when tired.
    
15. If you frequently have to travel after dark, or if your job involves visiting people at home, e.g. health visitor or a district nurse, consider getting a mobile phone or ask your employer to provide one

(Information - obtained from www.personalalarms.co.uk)