Will be different for every guy but here's my philosophy on it: It's a man's responsibility to teach his woman what he likes. If he doesn't dare to, that's his fault.

Let's say he's into anal. He just has to consistently do "assy" things to her such as lick her bootyhole to get it started and eventually it will spark her interest.

Talking about it or asking for it is not gonna be anywhere near as efficient as this.

He has to be the teacher in a non-verbal manner, because words are often more confusing than helpful to her.