This is the easiest way.
1. If you are still in the US, then you can inquire at your local police department for fingerprint services, or call your local FBI field office to make an appointment for prints. Prices vary based on who provides your prints. If you are in Canada, call your local Commissionaires office (
https://www.commissionaires.ca/en/national/home?postal_cancel=1) and make an appointment to get your fingerprints done. Tell them it is for immigration purposes and that you need 2 copies of ink prints. The cost is roughly 60 CAD for the prints.
2. Go to the FBI's electronic records site here (
https://www.edo.cjis.gov/#/) and fill out a request for the police clearance. The cost is like 18 USD per request. You will receive email verification with a link and PIN number to access your request online. Do NOT delete this. You will need that link and PIN to access your completed PCC once done.
3. Once you submit this, it will put your request into the FBI system. At this point, you need to mail your fingerprints in to the FBI. The address is provided for you when you submit your request.
4. Once the FBI receives your fingerprints, you will receive a PDF of the PCC in your email which you print out and submit with your application. Their turnaround time is about 24 hours from the time they receive your prints in the mail.