Ensure that your car is properly serviced as at when due
Before you leave home in the morning, confirm that your wipers, double pointer are working.
Ensure that your tyres are properly gauged.
When you are driving in the rain drive at reduced speed because the road is wet and applying brakes at high speed may not be easy.
Keep an appreciable distance from the vehicle in your front.
Be very careful when overtaking other vehicles particularly the heavy duty trucks and trailers.
If you are driving on a road you are not familliar with, it is advisable to maintain a low speed because you dont know where the pothole is.

src: http://www.tipslodge.com/2013/04/driving-this-rainy-season.html