The first step to joining the MBA programme at IIM Bangalore is to appear for the CAT and obtain a valid score. So you must put in maximum effort to score well in your CAT exam.  This will help you meet the CAT cut-off percentage of IIMB. Provided you qualify, you will be shortlisted for the WAT and PI. You have to appear for the WAT and PI rounds and if you are successful, you will get an admission letter to join the MBA program at IIMB. 

Each step requires committed preparation from your end if you want to join the MBA program at IIMB.