Hi Pradeep,
In general please remember that the additional essay is only to explain any gaps in your education or work experience. You can also use it to explain certain things that cannot be explained elsewhere.
Let me give you a simple list.
Do explain:
- a low score on IR or AWA score
- why you did not get your current manager to write the recommendation letter
- anything unique about your degree that needs explanation (including those who have already done their 1st MBA)
- something about work history that is weird - joining a company back within 6 months
Don't explain:
- another awesome work-related project
- how you have worked for an NGO
- your hobby or any kind of extracurriculars
- anything that is just "another" story
Hope this helps,