HI Kritikasinha30,
I've been accepted to HEC summer school 2019 both for the luxury management program as well as for digital marketing. Also, I've been accepted to IE and Fudan so maybe my profile will give a good overview of what works to get admitted.
My background is in Communication (BA) from a Swiss university. I've been a member of two clubs on campus and have also organized a few events for both clubs. I've worked for 4 months full time before starting my studies and have done 1 internship (event management for luxury brands) whilst studying. On the side, I've worked part-time for multiple companies. Additionally, I have started a small online shop for a short period of time.
I do not know what the "requirements" really are for summer schools and how much extra-curricular activities could play a role to the admission committee, but I reckon that good application essays can make a difference.
Would be very curious to hear from others who've participated in the summer schools either in HEC Paris or IE Madrid how the experience has been.
Hope this helped though in case you're still planning to apply