As many times UPSC has proved, there is no value for rotting facts & figures for Civil Services Exam. It expects people to have general studies understanding of the Indian society which includes history, geography, polity, Economy & foreign relation. All these aspects are to be studied in the current context which makes current affairs as the deciding factor for what needs to be done.
While preparing for general studies always ask one question that will common man with curious nature will have this information. The same question needs to be asked during the exam. If the answer is no then it is waste of time to spend your timing thinking about it.
So next question is what are the resources available for UPSC general studies preparation for common man? Newspaper, TV, Internet (atleast once a week), fundamental books from school etc. How one can utilize these resources for Civil Services Exam?
The newspaper is sources for current state of affairs and you prime source. Follow news which is important from the perspective of a common man & bureaucrat. When you see a concept like Inflation or WTO, go and find out more about it from the internet. This will help you in deeper understanding of the news & help you analyses it yourself.
The candidate must have his own viewpoint about different social issues. Here is a trick part, with such short timespan, how can one create his viewpoints? Follow television debates & discussions on radio, this will help you in finding out different viewpoints of bureaucrats, politicians, social activists etc. Always keep your stand neutral rather than favouring to one another.
Now the final aspect of General studies preparation is to bring creativity in your answers. Simplicity has always been rewarded by UPSC. That's where NCERT books come into play. They to use as generic language as possible. Being a bureaucrat, you are supposed to solve common problems and talk in a language which can be understood by everyone. Thus try to create as many diagrams as possible as picture is the universal language.
UPSC is a group of best minds in our country but is not looking for geniuses rather it looks for people with good social understanding with honesty & integrity. So don't be afraid if more engineers or MBA's are appearing for Civil Services exam, Just be honest and give your best.