I am a strength and conditioning specialist who works in a sports therapy clinic to help people get strong after they have recovered from an injury, or athletes wanting to prevent injury, and extend their career (even for recreational athletes).
Most trainers don't have a real plan for their clients and don't address their weakness - which leaves them at risk for injury. I fix their weakness, build balance, and progress them safely.
I watch their movement and create a custom strength and conditioning program for them, based on their muscle imbalances, schedule and available equipment. I then coach them through the exercise to make sure they are doing it right and feeling it in the right places.
I send them home with a detailed handout with pictures and descriptions, and they come back every few weeks to few months.
I am now extending this service internationally through my website. Instead of physically coming to my clinic, they will upload a video of them performing my assessment movements as well as information about their schedule, history etc. I will then do the same thing as in the clinic - send them a program (with video), and then either have a video call with them to go over it, or have them upload another video of them doing the movements - telling me where they feel it. I'll critique their video and maintain correspondence via email and the website.