I do play with my EQ6. I also use crayons and colored papers and other things as well. I'm pretty good with my imagination but sometimes you just see stuff differently when it is real...
I do a lot of looking at things. Seeing what other people do and learning from it, what works/what doesn't. I've taken a couple of college level art classes and I have several books on color theory, mostly from a quilting perspective. It doesn't have to be a quilt, it can be a painting or a sunset or a motor home or whatever. I also had a class on Logic in college, the instructor in that really helped me tie together a bunch of things and figure out how to analyze and evaluate what it is I like about something. He said that "if you know what you like, then you should be able to say what that is" and I find breaking things down helps me. When you know what you like/want and then the reasons on why some things work better than others, or how to get different effects, you are on your way.
I think the mistake that I, along with many others, made too much in the beginning was being too coordinated, too matchy-matchy. You need some pops. You need to vary scale. Especially when going scrappy, I now push the boundaries and put in something that doesn't really work just to show that you throw enough fabric at it and it all sticks. At the same time I know that some things always stick out, so you either have to know that and love it in advance or do something so whatever it is doesn't show so much.
I've mentioned the book Scrap Quilts by Judy Martin before, the patterns and techniques are pretty dated but I think the pictures and the discussions are still worth it.
https://www.amazon.com/Scrap-Quilts-.../dp/096029709X
There are many books, videos and seminars on color theory for quilters, I think this is a good start
https://shannon-brinkley.com/blogs/s...he-color-wheel