Go through your branch to resign your commission and then "enlist" in order to go through the 18 series pipeline.
The SF Recruiters at Bragg should be able to help you with this process.
Further, in order to ensure your highest chance of not getting screwed...your detailer at HRC should be able to walk down the hall and work with the SF folks so they are both on the same page as to getting you from point A to point B.
Your FIRST step, rior to anything else, would be to get yourself an SF Physical to make sure there are no issues there. Unfortunately, you will fall primarily under Chapter 2 (initial entry) as referenced by Chapter 5 (Specialty Physicals for initial entry into the program) versus RETENTION in the service.
Meaning, you can have things once you are in that are no big deal (i.e. pilots can wear glasses), but those same things will prevent you from getting in (i.e. pilots must not need glasses to attend flight school).
Hope this helps and good luck. Plan well for your pay cut.