This triple layering technique has been around for a while, and it looks gorgeous with the collage stamps featured in the Navigation collection.
This image is featured on the Collection UM.
The vertical collage with the ship's wheel is on the Borders & Backgrounds UM sheet.
You can vary the sizes of the artwork and panels, but here are the sizes used in the featured card: White art panels: 3-1/2 x 4-3/4", 2-3/4 x 4", and 2 x 3-1/4" Rust mats: 3-3/4 x 5", 2-7/8 x 4-1/8", and 2-1/8 x 3-3/8" The image stack below tells the rest of the story:
Keep this "Pinnable" on hand for the next time you're looking for a technique to try!