Hi Shivani,

For DI and LR, previous year papers are really important. It is highly unlikely that you will get a straightforward LR / DI question in CAT, or for that matter in any other management entrance exam, these days. But to become capable of solving those questions, you need to solve some easy questions first. 

Dedicate two days of the week to Logical Reasoning and Data Interpretation (one each). On those days (till July), spend the majority of your time solving basic questions, watching video tutorials for the hard stuff, going through the solved examples for previous year papers, etc.

Some books you could follow are-

• How to Prepare for Data Interpretation & Logical Reasoning for CAT (Tata McGraw-Hill) by Arun Sharma covers all the fundamental concepts of Data Interpretation and Logical Reasoning.

• Trishna's Verbal Ability And Logical Reasoning For The CAT And Other MBA Examinations by T.I.M.E. Publisher: Pearson

Good Luck!