I don't know what to tell you about carving it. To make the blank, I bought 4/4 basswood from Austin, about 8 feet long. I used pieces of two boards, and I think the boards were maybe 6" wide. To assemble them, you draw a line down one side and put arrows all going the same way. This is so that when you cut the basswood and put it together into the panel, all the grain is running the same way. It's bad to have a serious grain change at a glue line. You're cutting along and suddenly the wood starts splintering on you.
When you use two boards, you have to try to read the grain, or make some test cuts on both boards and select a direction.
Anyway, once you make your decision, you live with it. Cut the basswood a bit long and glue it into a panel. I used the big sander at school to sand it flat but I could have done it by hand with planes, or just left it because the carving would remove any mismatches where the boards join.
I took the panel to the clients house and made sure it fit. I had visited earlier and taken measurements but you know how that is. I made the panel just a bit large (about 1/8") and planed it with a block plane while at their house to get it to size. I *did not* want to carve the whole panel and then find out it was too small.
For the layout, I drew a vertical line and a horizontal line to divide the blank into 4 quadrants. To draw the design, I put the picture they gave me above the quadrant I was drawing on and just drew the design freehand. I used sandpaper to erase when I wasn't happy with it. When I was satisfied with the design, I used tracing paper, taped it down to the blank, and traced the design.
To transfer the design to the other quadrants, I put carbon paper on the quadrant and then used reference marks I put on the tracing paper (to align with the border and the horizontal and vertical lines). Then I just followed the design with a pencil which transferred the design to the wood. Repeat for each quadrant.
In carving it, I did not use a router. Basswood is soft and carves easily so it's fairly easy to excavate the ground areas. Also, a router gives a ground that's too "perfect", while a carving tool leaves some irregularities in the ground.
Even though I had the design drawn on each quadrant, when I carved it, I modified the design to suite my taste. If you look closely, you'll see that there are variations in each quadrant. The carving depth is about 3/16-1/4" except for the center flower which I carved deeper (I didn't measure it and can't do so now).
That's really about it. If you have some specific questions, I'll try to answer them. Remember the panel has been installed so I can't take any closeup pictures of any detail - all I can do is respond verbally to the best of my memory.
Mike