There are five basic things that are being assessed and checked in the ISSB

1. Your General Knowledge
2. Your Physical Endurance
3. Sense of proportion and Judgement
4. Leadership qualites ( to include power of decision, comradeship and others)
5. Your knowledge about your specific branch.


Any suitable person serving or knowing the forces will always advice you not to join any academy.

I will also go by the same
But actual thing that has to be done is to become familiar with the test.
Buy a DOGARS guide to issb to get acquainted with
If you think that you have developed a good acquaintance with the mechanism its very fine

Otherwise you may visit an academy for not more than a week to get familiar with.
ask further
If not clear.

Otherwise work on your General Knowledge
Dress outstandingly
remain very confident less over confident
Show extreme motivation
write down answer to questions like
10 good qualities
10 bad qualities
intro
why want to join army
etc and know that what you have to say

Best wishes with you..


Last advice covering everything is
Be natural , truthful and a very descent personality.

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Its not the time of triumph that matters rather its the time of trial that matters.