You can take a train to Varanasi from various cities in India or fly in on a local carrier too. They have an International airport and are connected to Thailand and other destinations too
I would avoid summers and winters. Autumn and spring is the best time to be there. Carry a tripod as the morning sunrise is one of the best in the world. Your March issue has it.
A memorable shot. Was walking the streets of Varanasi looking for something to shoot which others had not already done...After a long tiring Hot day I saw this saint walking the streets and it just refreshed me. His story was even better. Am planning to do a story on him later in the year.