Fun Stuff! Coincidentally (or maybe not), I JUST got through playing with a diaper-boi buddy of mine, 23 yr old preppy college student, so I MIGHT have some suggestions here to make it more provocative.
Don't worry about krinkle noises, only you and your friend will notice, that makes it more exciting. Smile at each other when you krinkle.
Have your friend diaper you naked sprawled out on the bed with the diaper laid out under you (be sure to get a DIAPER , not a pull-up, much more provocative), usually easiest with them sitting in a chair. If oyu have never tried it (or your friend), try doing "age play", call them mommy (or daddy) all night long and act immature like a clingy child.
If it is agree on, use baby talk for parts of the body and bodily functions.
When you go out, drink lots of liquids so you will need to "go". Tell your friend in little girl voice, "Mommy (Daddy)I need to go. Let them know that they should not allow you to "go" for a long time.
Wait until you can't hold it back, then tell your friend that you are "going on" yourself, watch each others' faces, smile, maybe lick your lips or some other provocative mouth action. (Daddy, daddy, I am going on myself!)
Do this and other stuff will come to mind. I assume your friend has a vivid imagination, as do you. Make use of it. Would it freak you out exchanging stories for your past? I find it very exciting.
How does that all sound? Too weird? Not at all, not one gets hurt! (Just look for other ways to ratchet things up. I love for my diaper boi to suck and lightly nibble my nipples. Try that with your partner, like you are baby girl in diapers.
Tell me if any of that works for you!
Dad