Pack some nice homemade food, cause this isn't a short trip !
There are direct flights and trains for this journey. Travelling by train is the cheapest way of getting there. New Delhi (Delhi) to Bengaluru (Karnataka) distance is 2140 km and you can get there by train in just over 36 hours and 15 minutes. However, flight tickets come also cheap with fares starting from ₹ 4663.
The temperatures at this time of the day are in a comfortable range.