This is a quick checklist of things you should consider upon arriving on campus:

For all incoming grad students, consider the following:

• Get MIT ID ASAP – the card office is located in the student center, and having an ID gives you access to everything, so you definitely want to do it earlier than later. If you live in a dorm, make sure you talk to the front desk after getting your ID and they will have you fill out a piece of paper and in a week you will have MIT ID access to your dorm building (before that you need to use your key to enter your dorm building as opposed to swiping ID).
• Attend the departmental orientation: watch out for emails from the MIT ANS presidents for events and such.
• Attend GSC orientation (optional): I mark this orientation optional because I don't recall learning anything specific from it. The dental insurance session is the only one I can remember, as MIT grad student insurance (the one we get for free) covers annual eye exam but does not cover dental, which means that you need to get a separate dental plan if you are not on your parents' plan. There are two available for MIT grad students, and both covers dental offices in Cambridge area.
• Sign up for a gym membership: grad students get MIT gym membership for free, but there is still a short form you need to fill out at the main desk of MIT gym before you can access the gym. They will give you a little red card when you sign up which allows you to check out a towel every time.
• Stop by a MIT library to activate your library account: the process takes like 5 mins.
• Set up direct deposit if you are going to be paid by MIT. You will probably get an email about this from the HR office.
• Consider getting an office if you are a PhD student. This does not need to happen right away as you might not need a place for research yet, but if you have a particular office that you want to be in (e.g., to with older grad students from your group), it might be better to request earlier than later.
• Consider transportation options if you live off-campus:
  
  1. Public transportation: MIT offers discounted monthly bus passes ($25/month) and T pass (access busses and subways for $37.5/month): http://web.mit.edu/facilities/transportation/tpass.html There is a MBTA chip in our student ID, so our ID acts just like a MBTA card, so you swipe it to get on any public transportation and can load money onto it through the MIT card office or using their website.
  2. Bringing your own car could be expensive due to parking expenses, so I'd consider ZipCar which has cars located throughout campus. MIT students receive special discount like no application fee, no security deposit and $25 annual fee which I think is a good deal: facilities/transportation/car_sharing.html
  3. Biking is the other option, though make sure you have access to in-door storage for the winter, as your bike will last through the winter outside. If you want a good deal, wait till Sept/Oct time frame where there is a bike aution at MIT and you can get a bike cheaply. Though please be extra careful biking in the Cambridge area – there is a spot at the intersection of Mass Ave and Albany St where an MIT undergrad was killed by a truck while biking a couple of years back. Boston/Cambridge area has some of the worst drivers I've seen in my life so I would not trust them to not hit you whether you are walking, driving or biking.
  4. Other ride-sharing programs listed on MIT's site: facilities/transportation/index.html
• Be happy!

Additional items for international students:

• Report to international student office at MIT right away: iso/
• Complete some stupid English test offered by MIT: MIT makes all the international students to take this listening + oral exams before semester starts. If you have spent any time in the States you would be fine. If not, you might want to ask one of the recent international student in our department for their experience – essentially they have some American slangs during the exam that you might not be familar with. If you fail this exam, you have to sign up for some ESL classes which I heard was worthless so you probably don't want to waste time on that if you can avoid it.
• Get a bank account ASAP: Bank of America is probably the largest bank you can find in the area (Chase does not have any location near Boston unfortunately). You will probably not get a credit card until you have a SSN, so just get the plain checking and saving accounts so that you can pay rent and get paid by MIT. The other option is MIT credit union, but I have never used it so I cannot comment.
• Get a cell phone plan: cellphone plans through major carriers like ATT and Verizon has been really expensive lately (roughtly $50/month/person?) so I got a google number and use SIP calls on campus where there is Wifi (you can call and text for free as long as there is wifi), and uses a service provider called Ting for data when there is no wifi. Though this requires some work to set-up so depends on how much work you want to go through...
• Get a SSN if you are employed (I think that means you have a RA or TA?): double check with the international student office on how this works...
• Get on your country's student organization's emailing lists (optional): sometime it could be beneficial to be on your country's specific MIT email lists for getting help and info specific to your nationality. For Chinese students, I think you are automatically on chn-all@mit.edu, and might need to sign up for chn-open@mit.edu( though this one has lots of spam so you might want to unsubscribe after a while).