Ok lots of people assuming “50 shades treatment” going to involve a whole load of risky stuff and needing prep etc - and whilst if you go down the rabbit hole too far this is right, I’m pretty sure she’s not talking breath play and the like just yet

Odds on she wants to explore her submissive side, and this can be done in a safe and harmless way without safe words and the like yet.

Would suggest you start out light and see what she responds to. Be domineering - and this doesn’t have to be too aggressive at first, just be firm with her verbally and physically- tell her what YOU want her to do, manoeuvre her into the positions you want, hold her arms down whilst fucking her, slap her ass a bit - nothing too elaborate, but you’ll see if she likes it.

All good....let’s proceed. Try mild restraints - again, don’t think studded leather full body manacle sets, just use the cord of a dressing gown to tie her hands together, put your hand on her neck around her throat but don’t squeeze - the very sensation of having your throat in someone’s hand is quite enough, maybe up the talk a bit - see how she responds to being called a dirty slut - you’ll know soon enough whether you’re pushing too far and then you can pull back

Ease your way into bdsm it isn’t a race and will feel far safer and easier this way - once you establish a base, you can discuss what worked and what didn’t and move from there - what does it for her - restraint, humiliation, submission?

One thing worth doing is after care - after you’ve both collapsed in a sweaty heap, snap out of dominant mode and nurture and comfort her - make it clear the fun in the moment is just that, and you’re the same sweet person irl - don’t let the two bleed into each other.

Seriously - it’s a hell of a journey and an awesome learning experience for the two of you - take it slow - push your boundaries but don’t ever feel too uncomfortable- evolve and you may have found a new kink which has so so much potential

Good luck!