It's probably a good idea to ask your university's career center (or whatever they may call it). I would imagine there are career fairs at your school, and that's often a good indication of when everyone else is applying in addition to being a good place to meet potential employers.
As a previous poster said, 7-8 months is about right.
It's been far longer than I'd like to admit that I went through this and things may have changed. But I recall the process being something like:
a) go to career fairs, give out copious amounts of resumes to any employer that looked decent
b) hear back from employers, setup on campus interviews for the ones you really want to work for
c) employers send current employees to campus to do loads of interviews
d) if you make it past that, go to an onsite interview at the employer
e) if you make it past that, get an employment offer
I did onsite interviews at three employers around the US, I think I remember accepting an offer probably around January or February, I think, for a May graduation.
Best of luck!
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