Ombre is a Dual Tone staining with a diffuse boundary horizontally,  when the color gradually changes from one tone to another. With Ombre dyeing you can turn a faceless, and monochrome fabric in a stylish and contemporary curtains.
You will need  curtains. You can make them yourself or make to order, and then it is relatively easy.
You will need a bucket or other large container, and fabric paint. You can adjust the color saturation of their own, changing the residence time of tissue in the paint and the depth of the dive.