Quick search didn't show this method, so here goes.
Breadboards are nice, no need to solder stuff together and then see prototype doesn't work and then start de-soldering....which can be long and annoying process.
Matrises are cool way to make custom displays, with multiplexing, but there are comprehensive guides about that, i won't bore you with that information (easy once you get the hang of it)
But, placing odd-spaced matrix to breadboard isn't easy. One way is to bend legs bit so it fits, and run wires underneath the matrix (you need most likely to bend legs anyway however when making permanent version to common-spaced veroboard)
This method allows to place matrix to breadboard, without bending legs pretty much at all, with breadboard strips seen on both sides of matrix.
Step 1: Rig the Breadboard (but Not Permanently)
The trick is simple, when placed together, breadboard allow bigger space to maneuver components around. To make things better for matrix, use sharp knife and cut other of middle one power buses out (don't pry that double-sided tape, you might risk taking power connectors out) . Then matrix'll fit to center row, as seen in intro photo. There is one downside, matrix takes workable space from ic's on both breadboards, but that's small problem.
Other thing is that there are coupe different size of breadboards, these what i used are about 5cm wide, and accepts YwRobot-power adapter. Test and see!
The end :)