I haven't had much experience to draw from, so there may be other things that elicit the sub in me, but praise and encouragement make me stupidly submissive, while brutish bullying has the opposite effect. i suspect the latter may have to do with a childhood filled with bullies and feeling powerless and abused (i know, some subs aspire to this, but for me submission is something i give, not something that is taken). As an adult, i practiced martial arts for 25 years, second degree black belt, and would pity the guy who pushes the wrong button.
i went to Palm Springs a year ago and stayed at a gay resort. A Guy approached me and started talking with me. After a bit, He said He had to catch a plane and i asked if i could suck Him first. He was happy to allow and stood in front of me and immediately guided my head to His crotch. He wasn't rough, but definitely took control. We were outside (clothing optional resort, sex happens outside all the time) and He stated He wasn't used to doing things outside, so i invited Him to my room. On the way to the room i quipped: "You seem to have some Dom tendencies." He didn't say a thing, neither acknowledging or denying what i said.
When we got back to the room, we undressed and He sat on the bed, leaning against the headboard and parted His legs. i automatically lay between them and began to suck His 8-9 inch, very fat cock, a definite gagger. He took complete control, telling me how to suck Him, often guiding my head, but was never forceful or rough about it. It was like He was coaching me, saying things like: "that's it, you're doing great, just a little more, take it around the curve...." When i would do something He really liked or followed instructions as He gave them, He would practically gush: "good boy!!!" Or say things like: "aren't you proud of yourself?" He also would often ask me questions when my mouth was full and He knew i couldn't answer well, but still nonchalantly expected i would try... which i did. His approach had a combination effect on me of embarrassing the hell out of me and making me proud and happy at the same time. i think i was probably embarrassed by how proud and happy i was at pleasing Him. He stayed the weekend with me.
Several hours later He took me to dinner and as we were walking down the sidewalk together, He'd sometimes reach over and slide His hand in the back of my pants and run His finger up my crack. i just wanted to melt into Him, i was mesmerized by Him and fell really hard for Him.
It's funny, He wasn't a Guy who would have turned my head visually, it was all personality and chemistry, i was consumed with the desire to please Him.