If you want to be an independent trainer you need to get a teaching qualification (if you don't already have one - don't want to make any assumptions here!) then you can write the course including the lesson plan etc and submit it to insurers for accreditation.
I don't know how Babtac market courses but I do know the Guild have an online training directory so people looking for training can put in their postcode to find trainers near to them.
The Guild also offer the teaching qualification on a correspondence basis I believe.
Good luck