The Vote.gov website has a breakdown by state. Nearly all states put the deadline 30 days or less before Election Day (Nov. 6), so you most likely have until October 6 or thereabouts to get registered. Some states are more lenient. In North Dakota, you don’t register at all, you just vote; but, let’s face it, you probably don’t live in North Dakota.
You can register at Vote.gov.
In not-unrelated news, I am reading a book called Why Nations Fail. The book is thick enough to stop a bullet, but the gist is pretty simple: nations succeed when the general public participates in decision-making, and they fail otherwise.
This concludes our PSA.