I just don't see this going well, I couldn't hide it from my boyfriend even if I tried, my anxiety would give it away. I'd be having so many panic attacks from the stress I wouldn't even be able to work anyways. I talked to my bf about starting escorting and he agreed to let me try it (still in the research phase haven't started escorting yet). The reason he agreed to it was "I won't really know how I feel about it until you've done it" So basically he's going to see if he can handle me escorting even though he doesn't agree with it. Why? because he loves me and it's my life to do with what I please. I don't let him control me, even when he tries I'll call him out on that BS.
Hiding it, WILL hurt him because eventually he WILL find out, all lies are ultimately caught. Whether it's sooner or later. And the escorting part will hurt him the least, the lying will be the most traumatic thing, you could give him trust issues and possible ruin future relationships for him. How anyone could choose to do that to another person is beyond me, but everyone has their reasons and I won't judge. I just hope you consider his feelings and the long lasting effects your actions can have on him.
Maybe just get this one client out of the way and then have a full discussion with him. It will be hard, it can be emotional, but explain to him how this is what you want to do with your life and clarify that doing it doesn't make you love him any less, it's just work. If he doesn't agree, I would either respect his decision and not do it or keep doing it and move on without him.