Care and creativity! But the trust can be essential to many of us even to reveal possibilities...
You can start with a fantasy or with one tiny sexy bit and grow, shrink, and adapt from there.
I was feeling sexy and wanton and I told my woman that I wanted to pleasure her out by a playground we'd passed. Just a couple days later we took a walk over to that area, walked a while, and while returning (having seen no one) she pulled me aside to the playset, then pressed me to kneel in the snow at her feet, covered my head with her skirt, and <3 heaven <3
Or it can be spontaneous/effortless - I don't recall why or how it happened, but one summer weekend we were by the lake with many other people, and my Lady held my hand and whispered things making me aware that she was actively teasing me sexually in front of others. Sitting down it only take placing her hand on my thigh to raise my awareness and slight humiliation even further.