I'm submissive, it doesn't have to involve pain, but pain is good. Depends on whether it's controlled. I don't like someone being rough, rough is just careless and clumsy.
Humiliation maybe?
For me, I like submitting, but not to some unsophisticated oik who likes being careless. For me it has to provoke emotional responses of helplessness, mild fear (anxiety of surprise) but also dependency, and feeling so close to someone that even my thoughts are not my own. And it has to involve lots of talking, lots of psychological play, and preferably 'he' shows self control.
It's ultimately very easy to control other people, what is much harder is having self control. It shows a level of emotional maturity and confidence that few people have, and it's worthy of respect.
Full time Ds relationship, but my independence asserts itself as my ability to think differently, to always be of independent thinking, to say as I wish, to be who I am. And the only person to whom I submit is DP. I respect him. I respect others as individuals, but I don't give a shit what anyone thinks of me when I refuse to agree, but his opinion matters, his validation matters, I seek his approval, his only, and I want only to please him. That is the foundation. And without that, no amount of having my bum spanked or my nipples clamped would work.
If he's a newbie, just make certain that he wants this. No use persisting or converting. You'll only end up topping from the bottom and undermining what you seek to achieve. A friend of mine does this in every relationship and then wonders why the man doesn't want sex, and becomes a sad, helpless, submissive wreck, incapable, and completely lacking in confidence.