Here's how I did it...
I painted 1-3/4 inch wood dowels and then cut them, using a miter saw, into blocks (1/4 inch, 1/2 inch, 3/4 inch and 1 inch thick). I then sanded any ruff edges on the blocks.
Next I used a hot glue gun to secure the blocks to a pre-cut, thin piece of plywood. I alternated the placement of the different sized blocks for a cool 3-D stair effect. Once all the blocks were in place I touched-up the paint on them.
These flower pictures were originally one that again, I cut in two.
The next piece was done a little different, but it's still the same basic concept.
I used 1 inch dowels for this piece. I fastened them together using a brad nailer.
The next time I make one I'll take pictures for step-by-step instructions. This is a time consuming project (The London pieces took a total of about 11 hours). I think the end result is worth it though!