Most of the time, USCIS will schedule you for an interview after your background check is completed. But sometimes it may schedule before your background completes. This depends on the Field office that your petition is handling. You can find your Field office in here. But if your petition is simple and straightforward, your interview may be waived and directly get the approval.
USCIS will send you the interview letter through the mail (or they will call you or email you if they want to schedule quickly). In the interview letter, you can find the information you need. Also, you may find the requested documents (sometimes, they will send you a generic interview letter that has some other required documents. In that case, don’t worry about it and take all the original documents that you sent with your application).
As the biometrics, you need to go through the security in the interview location. You can not use your mobile phones. So, leave all the unnecessary things outside before you enter this building. Once you passed trough the security you may sit until you are check-in. Once you checked-in your interview officer (IO) will come and take you to his/her office or interview room. First, IO will ask you to take the oath (you agree to tell the truth). Then IO will ask questions or request any original documents. make sure to bring a government issued ID such as drivers license.
Once the interview is over, you may be approved on the spot or given a interview completed notice. The the IO will request your file from KCC (electronically) and Visa number. If everything is good you will see a status change in your myUSCIS and egov accounts. Some IOs will request your file from KCC in advance. You can find this by calling KCC and ask if your Field office has requested your file or not. If not during the interview, politely ask your IO that if he/she has request the file from KCC.
Tips for the interview:
Dress properly. Try to wear a formal dress (e.g. long sleeve shirt and trouser for men) but don’t overdress either.
Talk to the IO politely, never argue with the IO. If you disagree with the IO, tell it politely or ask to talk to the supervisor.
Review the applications forms you sent with your application. Remember all the important dates such as date of birth, marriage, address change dates.
Prepare to answer questions relate to the purpose of immigration.
Answer with precise and short answers. Don’t talk too much (whatever you say will be used against you).