I started out by researching what products did what for our hair on the Internet (before the hair boards) and then I talked to hair stylists for predominately black clients about what they use on black hair and what works. That's how I discovered some of the Nexxus products. I only used the shampoo and moisturizing conditioner for a few years (Botanoil and Humectress). Didn't know how to use anything else until I came to the hair boards and learned about other products like leave-ins. I could tell the products worked on my hair because I was getting compliments and my hair felt better. I didn't know how to care for my hair yet.
Now I have confirmation that the products I used are good ones for me and after giving up the heat, I can really see what the products are doing to my hair. My texture has changed and I have only minimal shedding and no breakage. I can identify which product worked because I started out with just two, shampoo and conditioner and gradually added products, like the leave-in. So then I could see how and if the leave-in helped or didn't help. The key is not using all those new products or procedures right away, gradually introduce them one by one and wait. See how the hair feels and whether or not hair is breaking off or becoming dull because of a product. Or whether hair is thriving and is shiny and thicker.
Procedures like co washing and hot oil treatments are extras, IMO. I would get used to a regular regimen like shampoo and deep conditioning, perhaps a leave-in until I have mastered it and my hair looks great time after time. Then add something different like a hot oil treatment and see and feel what is different about that.
Some products you can tell right away that you will not use it ever again or that you and your hair loves it. At other times, it takes practice and patience. Again, get your basic regimen down first. Then one step at a time, one new product or procedure at a time and if it works, make it part of your regimen. If it doesn't work, it may not even be something you need to do.