You need to let her pick her own fabrics. I have taken the kids to Joannsfor the variety and then guided them on color choice, which ia a part of quilt making.
Of course the first step was choosing a pattern. I gave a choice of two like maybe a 4 patchwith solid squares inbetween or a fencerail with large squaresinbetween. For a beginner you don,t want them to lose interest by having them cut too much!