I started with the cat silhouette, cut roughly free hand and then made slight modifications as I went along. I used three pieces instead of one to make it a bit more adjustable for placement on the window.
I used the same 1 part modpodge and 9 parts water solution as my original mosaic as it has held up very well. I used paint brushes, medium sized such as you would use for acrylic painting, to apply the solution.
I set the cat low on the window, right atop a crosspiece so it will appear to be on a ledge from the outside.
Then I started tearing tissue into large chunks for the background layers. Starting at the top I worked downward through four shades of vibrant greens.
The last color layer I used as a horizon of sorts for the cat to sit on.
At night, from the inside.
At night from the outside.