In Autumn and Winter Quarter:
Check your major program sheet and talk to your department to ensure that you know exactly what you need to complete the major by spring. Ditto for minors, honors, etc.
Check which GERs you’ve completed and which ones remain. Be sure to review the Degree Progress Report in Axess--that is the official list that the Registrar will be using to clear you for graduation, so ensure the record is correct.
Information about accessing your Degree Progress Report and checking your outstanding Ways requirements is available on the Check Your Ways page.
Check your units. You need at least 180 earned units to graduate. At the bottom of your transcript, see the line “units completed toward undergraduate degree”. That is the total that matters. (Outside credit on your transcript -- AP, IB, or transfer -- counts toward the 180 total in addition to units earned in Stanford classes.) Note, however, that there are limits on the number of activity units (8) and units taken for credit or satisfactory grades (36) that may be applied toward the 180 units required for graduation.
The Registrar provides excellent guidance in their Graduation webpages. Consult a UAR advisor (Academic Advising Director, AARC advisor, or Sweet Hall advisor) if you have questions about GERs or units; consult your major/minor/honors department with questions about department requirements.
In Spring Quarter
Make sure you are taking all the necessary courses as above. Then consult the Graduation Checklist on the Registrar’s website for important steps and deadlines. You'll need to Apply to Graduate early in the quarter.
Throughout spring quarter, the Registrar will periodically audit students who have applied to graduate, and will notify students who do not have the appropriate requirements in progress. Pay attention to your email! Important announcements about graduation may come from StudentServicesCenter@stanford.edu, DegreeProgress@stanford.edu, or Registrar@stanford.edu.
For details about the ceremony, caps, gowns, and so forth, consult the Commencement website and pay attention to emails from your department.