You've pretty much described my hair pattern to a T. Welcome to my world.
A lot of people here take care of wavy hair the same way one does with curly hair (detangle in the shower, don't touch it as it dries... etc), but I think with this kind of mixed hair, a different approach is needed.
This is my routine:
Comb freshly conditioned hair with a wide tooth comb
Put in some sort of oil, leave-in, whatever.
Comb through again, maybe with a finer tooth comb if you prefer.
Let it air dry to damp, fluffing it with your fingers to help it along.
Then comb it into a bun on top of your head.
Leave it alone until it feels drier
Take it down
Comb again if you like, maybe add just a touch more oil/product.
If it is still too damp for your liking, let it dry loose some more and then put it up in a bun again.
My hair ends up drying into loose and smooth bun curls/waves which are pretty uniform. Sometimes a lotion-y leave-in leaves my hair a bit more fluffy and frizzy than I like, so I prefer adding oils/shea butter.
Keep in mind, this routine is an evening affair. If I end up washing my hair in the morning, I don't really take it down from its damp bun until evening. I'm fine with it, but others may find that annoying.
Good luck hair twin, or at least hair sibling!
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