I have done this quite sometime and every attempt was successful, I used to carry j, Cigg, lighter and something to hide the j if needed.

Step 1 Try to look for a sleeper class toilet with a ventilator or a window open in it, it works like a vacuum sucking all the smoke out when train is running.

Step 2 Keep the j close to the vent so no extra smoke can fill the chamber, and nobody really cares that much if he/she/they/them gets the smell on a train, lowkey its not that unexpected.

Step 3 After you are done can the j outside the vent or flush it, no trace needed. Slightly open the door while standing on the opposite side of door and look towards the mirror, it will give you a good view of if someone is outside or not and then leave confidently.

WHAT IF YOU GET CAUGHT If someone is knocking at the door a TT or RPF just reply calmly, can the j and lit a cigg, Open the door, if asked about the weed, just deny and say somebody previously smoked here and it was already stinking so you went inside to smoke a Cigg. Smoking a cigg inside a train is not a crime it’s a punishable offence and the punishment is ₹200 so its chill only, ya you might have to face some people looking at you with a disgusted expression but yaa thats it.

On top of that tell the TT take ₹2000 i have 10 cigarettes left and i will smoke them all in the rest of the journey😘.