Check your speedometer regularly,
especially when coming off high speed roads
Modern cars are so powerful and comfortable they give drivers little sensation of their speed, so many drivers find themselves exceeding the speed limit without realising it.
This is particularly true when coming onto a lower speed road after driving on a high speed road for a long period. It can often feel like you are moving at a snail's pace when you reduce your speed to 40 mph or 30 mph after coming off a motorway or dual carriageway. In reality, 30 mph and 40 mph are still very substantial speeds and a pedestrian hit at those speeds will be seriously injured, and quite likely killed.
It is misleading to rely on a 'feeling' of speed. The only way to be sure of your speed, and to check you have reduced to an appropriate speed (even if it 'feels' slow) is to check the car's speedometer regularly. Although you should never rely on 'feeling' your speed, you may be able to improve your judgement of it by regularly comparing how fast you think you are driving with what the speedometer says.
Many cars now have speed management devices that allow the driver to set certain speeds and receive a warning when they are being exceeded. If your vehicle has a pre-set speed function, set this so it will warn you if you exceed certain speeds.