To Apply for your Social Security Number (SSN) you should first make sure you have a bank account set up. You will need to collect your Immigration forms, APIA documents, and passport. Then you must make an appointment at your local Social Security Administration (SSA) office for an in person visit. No walk-ins are accepted. You can also chose a location that is a bit farther away, if the appointment dates at your local office are too far in the future and you don’t want to wait that long. You will need:

Your Passport with your visa inside
Your DS2019 from APIA (in your email)
Your APIA participation letter (in your email)
Your I-94 for (download from https://i94.cbp.dhs.gov)
Your most recent bank statement (with your name and your Host Family’s address)

When making your appointment online, you can fill out all the forms on the website, this will make your visit much smoother and shorter.