Original sentence: Experienced motorcyclists who might be interested in becoming "RiderCoaches" should contact their states'  Motorcycle Safety Administrators for information on applying for certification.MSF's courses are taught by instructors, or so-called "RiderCoaches," certified by MSF and who, in turn, are trained by "RiderCoach" Trainers certified by the MSF directly
Edited sentence: Certification of experienced motorcyclists as coaches is handled by state Motorcycle Safety Administrators.MSF's courses are taught by instructors, or called RiderCoaches, certified by MSF and who, in turn, are trained by "RiderCoach" Trainers certified by the MSF directly