You will receive an email from Equifax with instructions to begin the I-9 process. Once you receive that email, please schedule an appointment to complete Section 2 of I-9 in person at 221 Whitney Avenue prior to your start date. You will need to bring original, unexpired, and printed documents to your appointment for verification.
Section 1 of your I-9 should be completed prior to your Section 2 appointment.
See Submitting Your I-9 Form for more detail.