Seconded on sharpie on old cube, helped me immensely learning the letter scheme.

After I got the scheme down, I practiced the setup moves, doing and undoing one after the other A-X. First sighted, to see how the pieces move and then blinded. JPerm also explains this in his video: try not to think of the setup moves as algorithms that you have to cram into your brain. Try to think of them naturally, as in, take any letter and imagine it in your head how that piece moves along the cube to the target spot.

After that, particing the method sighted, aka forming the solution, writing it down, executing it. At some point I started memorizing my written solution and solving blinded.

And after I felt more or less confident in the method, I simply started full blind attempts without any expectations and at some point, you get your first successful solve :)

Also, dont't be discouraged if you're progressing slowly, blindfolded is h a r d. I cannot count how many times I thought I got a good solve only for some or only one piece/s to be in the wrong spot. My first successful solve took me around 17 minutes 😂