Step 1:: Create a new document, mines 500x500. Take your rectangle tool and make a rectangle as long as your document and as wide as you want.
Step 2:: Go to where your layers are and right click to duplicate the rectangles you just made, do so to how many colors you have in your scheme. You will now have to use your arrow tool (
) to move each line next to each other like so:
Step 3:: Once you do that select all layers, right click and merge all layers. Lastly, go to filter > distort > wave and match your setting to mine. The lines should look like the second picture:
If this tutorial helped, a link back is required.