The SBI Clerk exam is an objective-type exam. You are not required to study everything in detail. Just sound knowledge about the basics is enough to clear the exam. After all, the objective of this exam is select smart candidates and not bookworms.
When it comes to logical reasoning, problems on seating and arrangement is a must. Though the problems are long and requires a lot of time, the right solution will fetch you 5-6 marks immediately. It is just like investing time to get guaranteed marks.
About 80% of the candidates ignore general awareness. This is where you can make a difference. All that you are required to do is read newspaper and dig up news which are about 6 months old. Country-Currency, Sport-Title, Book-Author, etc., are some of the favourite areas of the examiners.
If you are aware of computing tricks, then you would save a lot of time for yourself during the exam. Usually sums on arithmetic are easy to solve, but need a lot of calculations. If you can calculate faster, you will definitely have additional time to solve other questions.
Preparation is an important part for the candidates, but so is health. Do not forget to have timely meals and rest. After all, it is more important to appear for than to clear it successfully. Each year, about 1000 registered candidates miss their exam due to health issues and you surely do not want to be one of them.