What worked for me is taking the Wellcoaches 13-week course. I found it to be extremely indepth.
We met via telephone for 1.5 hours over thirteen weeks. All the students were required to apply the information they learned throughout the course by coaching someone throughout the 13 weeks.
At the end of the course there is a theoretical exam as well as a practical exam. In order to sit for the practical exam one must coach someone for three months and it must be documented for them to review. Wellcoaches has their own portal where you can write your client notes etc.
The practical exam requires that you coach someone for 1/2 hour using the Wellcoaches coaching approach. The individual you will coach is one of the instructors who lead the course.
After you take the course you have one year to take your exam.
I have only positive things to say about Wellcoaches. Taking the course has truly been beneficial to my career and has helped me become a more proficient fitness professional.
Hope this is helpful to you.