Attempt the subject you have good hold in and about which you are confident first.
Give equal time to all.
Cut off for each subject is below 20, but overall cut off depends on the level of the paper
and this year it was 190 and last year 172 I guess.
Don't lose your confidence there if the paper is difficult because if its difficult then its for all.
Try to attempt so many question so that you can score around 200 first and have cleared the
the cutoff for each subject, then gear up yourself for scoring a good marks in order to notch
up a good rank.
Wait for the reply of seniors too
Best of luck.