"yeah., but how do you advertise those kind of services? very risky. you cant just put up a sing or hand out flyers that say " steroid guru/personal trainer/nutritionist 4 hire" .."
Friend of a friend, word of mouth.
Believe me, when a guy adds 15 pounds of muscle while dropping 10 pounds of fat, and does it 3 months, everyone he knosw is going to be be asking him how he did it. Spose he gets a discount on his own services for everyone he refers.
Or, if the PT gets cash hungry and needs to add new clients, he can just start small talk with the regular, white collar 25 to 35 year olds he sees at the gym consistently. he knows what they drive and knows they're not cops from small talk abotu work, etc. Wouldn't take more than 5 minutes of conversation to work things out.
People that have the skill of hooking up, teaching to use, and keeping successful people from getting their hands dirty are always in demand.