This post has been inspired from: Remove cold without medicine - An excellent writeup by Bhavya Gandhi.
I read his post in April 2016, changed my daily routine as suggested in his article and well - it worked!
Earlier, once in every 3 months, I was used to get hit by cold. Cold would block nostrils for at least for week, and then would go away naturally. Apparently Bhavya had same issue. I followed his suggestion, now it is August 2016 and I'm yet to experience cold attack!