When is a good time to start selling my coaching services if I am coming to the school in September?

I am signed up to come to your coaching school in September and I am so excited!! I really want to hit the ground running after my certification so I am in the process of getting my website set up, will be starting a podcast soon, and have gotten my LLC licenses, bank account, etc. I want to start coaching as soon as possible but feel I need to wait until I’m certified through your school. I hope to use the next few months to build up a following and start to let people know of the services that I will be providing. When would you recommend telling people I am going to start coaching and letting people start signing up?