@lilin,
Telling him is probably the easier part, genuinely, bc if he's already kinky and dominant (which you said yourself) then he's not going to be thrown by you having a specific thing you want, he might even be into it once he understands what it actually involves.
Most people who are genuinely dominant pick things up faster than you'd expect when they're motivated, and "my partner really wants this" is usually pretty good motivation... it might not be perfect the first few times, but that's not a reason to not even start.