In this work, you start by painting a window with a very thin paintbrush. I used black. Just draw the basic lines of the window.

With a wash, apply the ink to paint the wall, but leave some whites in your paper.

Start doing dots and dashes that represent the flowers of the window.

Splash the ink of your paintbrush in the area of the flowers. You must use many colours.

apply some washes of black to better the window and clean some spots you don't want

This is the final result, dry and without the scotch.