I love Bargello quilts and have made many. One thing that has helped me is when I think I have the colors right I fold them and overlap them in the order I think they will be into 1-2”;strips, lined up so I can see how they actually look in the order of the pattern. Then you can see if something is too light, too bright, too….whatever. When you are pleased with the (run) label everything. The most important step to a successful Bargello is organization - label everything- I use numbers and letters keeping things in order. It’s really easy to turn something wrong, pick up the wrong strip or reverse something. Your quilt will be beautiful!