One of the most erotic experience with a provider was something very simple but is rarely done. (In my experience anyway)
The action was simple. She slowly took my clothes off. Whether conscious or unconscious, she gave subtle signs and gestures of the up coming event. Didn't say anything but stopped me from undressing myself. Slow teasing movements timed naturally with almost continuous eye contact. She wore a shear nighty with something interesting on underneath. She started with unbuttoning my shirt then... I'll spare the details but I was shocked at how erotic this was.
You might try this on a dude with a little trouble getting to full mast. Cuz that was all it took for me.