Most DI questions will consist of a bunch of statistics, numbers & diagrams that might look scary, but are actually not at all difficult to solve. In fact the trend has been: the scarier a DI set/caselet looks, the easier it is to solve. So before you lose heart & move on to an easier-looking set/caselet, scan that scary set & the list of questions in it. There will be at least of couple of “sitters” (questions that can be easily answered).
Improve your Calculation Skills/Speed: The Date Interpretation section is calculation-intensive. Such calculations can eat up your time. It is imperative, therefore to get very, very comfortable with calculations. Learn shortcuts that will help you calculate in your head.
Get familiar with all types of DI questions: When you have been practicing DI questions for a while, you’ll begin to notice that there are different types or formats of questions in this section. There will be bar charts, tables, pie charts etc. There will also be questions where a lot of text/information will be provided in 1 long paragraph. Also try reading business newspapers which have articles that are data-intensive & have graphs & pie-charts etc. After reading the article, try to mentally collate & analyse the data provided in them.
Practice, practice, practice: With a very good amount of practice your speed and confidence will increase considerably.