This coastal window treatment idea is to dye for. Dip dye curtains inspired by the Color Palette of the ocean.
From PBTeen
These oceanic dip dye curtains are available in turquoise, as pictured, and in bright blue.
DIY dip dye curtains for a Poster Bed using Ikea panels. Original source no longer available
How to Dip Dye a Curtain Panel:
Get yourself a bucket or bin and blue fabric dye. Dip the lower (and/or top) portion of the curtain into the blue water. Lift the curtain out slowly to get a gradient effect with the lowest part being the darkest. It is best to use 100 percent cotton curtains for this project.