What paper work do i need to fill out to request K9 ASI for U.S Army?

I have been in the army for about 4 and half years now and I am also a SPC looking to get K9 as an ASI. I am a MP been a MP for almost 2 years got road experince and also experince as a MP attach to 11B.I would like to request to go to K9 school but dont know the paper work i need to fill out. I heard I got to talk to my MP Bn SGM how ever im currently in a Infantery BCT so im in just a small PLT of MPs. Im just looking to go to school for the ASI so later on down the road if I go to a new duty station where I work the road I can try to get into the K9 section in that unit if possible? thank you