Hello Anurag. The preference of choice filling could br CSE then ECE then EEE then Mechanical then Civil and then Chemical according to me depending upon the scope of the branches in future and also according to the Placement Statistics of all the courses. Further depending upon your interest you can chose any course to be on Top or Bottom.
All the Best.

Hello,
You should set the branch preference according to your interest.You can check out all branches information from google and find out the branch in which you think you have interest and want to gain knowledge in it and then set preferences accordingly.
Good luck.