Pink, I think your hair has tremendous potential. It is nice and thick and doesn't look damaged.
The best advice I can give is to read up on the 2 forum and try methods one at a time. Since co-washing didn't work for you, buy a gentle shampoo, perhaps one for colored hair even though yours isn't colored, and dilute it with water. The try a light conditioner, nothing too rich, preferably without silicone of any kind. Scrunch with a liquidy gel, also without silicone.
Dry with an old t-shirt or paper towels. How does it look? Keep a little, easy, journal. Next time, try the same thing and diffuse. Next time alter one thing - perhaps try the twirling technique, or one of the other techniques, or if you can afford to try out some products, try a light mousse.
Mostly, reading will give you ideas. See if you can find someone whose hair looks like yours and copy what they use in their signature.
It takes time and patience - trial and error. Post back and ask specific questions. Best of luck!
2/c and some 3A. Modified CG.
Highly porous. Color over grey.
Best 1st day method: Super Soaker
Conditioners: Curl Junkie Beauticurls Strengthening Conditioner,
Deep condish: Curl Junkie Curl Rehab
Stylers: Experimenting with cones & sulfates while the dews are high. Sometimes try roller sets - classic glamor but I prefer my curls.
Every day is a gift