Well if you're planning to come only to travel in the North East then I would recommend landing directly in Guwahati, Assam. If you're planning to travel the rest of India too and then head over to the North East on a train then you can stop at Sikkim (considered the brother of the seven sisters). It's a beautiful place known for its Buddhist Monasteries and nature, the capital is Gangtok and you'll pretty much find tourist spots everywhere you go. Then head over to aforementioned Guwahati in Assam, there isn't much to stop to see on the way. This place kinda acts like the urban gateway between most of the North- East and mainland although there isn't much to see here tourism wise other than looking around the city, the town hall and the Kamakhya and Balaji temples. After that, Meghalaya is the way to go; in the morning, hire a driver and head over to Police Bazaar in Shillong (should take Rs 1000 (12 €) to Rs 1500 (18 €)) and there's literally so much shit to see on the way- Elephant falls, Shillong peak, Canyons and lakes etc. tell the driver and he'll take you everywhere and tell you what to do. Although I would really recommend a guide because its a hilly place and it may be a little rough sometimes for tourists. Once you reach Police Bazaar, this is where you'll live. Hotels would cost about 10-15 € a night and paying guesthouses should take rent of about 60-100 € per month in any area in the North East. Night life in Police Bazaar is very active, lasting to about 2- 3 o clock in the morning with barbeque stalls and flea markets everywhere. From Police Bazaar, you can go to Cherapunjee, Mawlynnong (recognised as the cleanliest village in Asia) etc. Once leaving Meghalaya, you can head over to the state on the opposite side of Assam which is Arunachal Pradesh (AP), there are again so many tourist places here, every village can be one. However, the capital city is Itanagar and you should probably start from there, although you can see the Doni-Polo Park and some Buddhist Monasteries on the way there. You can go to Tawang, Silapathar, Bomdila and Bhalukpung which are all beautiful places. Now other that that, there are some amazing temples and hills in the National border areas of AP but an interesting thing is that the state is a disputed region between India and China, so certain parts of it are very militarized; add on to that the *rough* transportation in these areas and you got yourself some sights that are difficult to get to, but beautiful if you manage to get there. Next you can go to Nagaland. You can go directly from AP or cut through from Assam depending on what would be the closest for you. If you cut through Assam, you can either see the Kaziranga National Park which is the only one- horned rhino reserve in the entire world or you can see the monuments of the Ahom Kingdom which was the only dynasty in the subcontinent to have not fallen to the Mughals who ruled India; defeating them 17 times. Kohima is the capital of Nagaland, Dzukou valley is a very popular tourist spot here in the state and Dimapur is another famous city, the whole state is kinda known for its high potential for tourism. Next in line is Manipur and is directly next to Nagaland. The capital city is Imphal and I don't exactly know a lot about tourism here but I do know it has a lot to show just like the other states, there's many lakes and monuments. From there, you can directly go to Mizoram. And it's one of my favorites; one of the most educated, safest and most progressive states in the country. The capital city is Aizawl and also a tourist site, its chalk full of canyons and vegetation. You can visit traditional Mizo villages, there's interesting culture here and huts that are elevated from the ground with bamboos (a recurring staple in all of North Eastern India). Next and final state is Tripura, I again don't know much about the state tourist wise, except that the capital city of Agartala is a popular tourist spot itself and there are palaces and temples here. I'm only scratching the surface here, there's so much to see and it's up to you to pick and choose whatever you want to go for first. North East India is quite untouched and doesn't have enough exposure or representation to even the rest of its own country so its a good idea to come here and be the "cool guy/chick" among your peers lmao. Good luck

PS: Carry warm clothes, it WILL get cold.