Much the same as those before me!
Sometimes I see a piece of fabric I love .... and then use it to create colour combinations for other projects.
Another place I turn to is wallpaper. An interior decorator taught me that when I am trying to put two colours (ie two rooms in my home) together that really don't go together, look for wallpaper that has the two colours, and let it be the transition. It worked in my home ... and now I use it for fabric too!