What's your definition of long?
I had waist length hair until a month ago and found that nothing, no products etc could really give me much curl. I'd get little curly ringlets at the end, very loose waves in the middle but FLAT TOP which I hated. I never did diffuse my whole head coz I'm lazy and I have thick hair and it would have taken a long time. But all the weight straightened out all the curl and most of the wave. And it took FOREVER to air dry .
Then I got layered cut to BSL with layers to shoulder length. I feel like I have short hair now since losing a foot was drastic. But everyone still thinks I have long hair!
I have to say that I love it shorter- all the products actually work now!! I have lots of curl - the cut took me from 2a in front and 2c in back to 2c in front and 3a in back!! It's really fun and flippy now. I had waist long hair for 12 years!!
I m not advocating a cut- but I do suggest layers if you want more curl. Hellisto has beautiful long layers-- so does curly in FL. I think layers really help with curl.
Also- I still have a flat canopy/straighter hair on top and IT IS REALLY A PAIN!!! Considering even shorter layers to get rid of even more weight......So I appreciate the comment on how do we handle that- I'd love to have the straighter part under. Oh how I long for root curls and volume!