Splitting the Billets
Braces for the guitar will be made from these billets.  This coarse-grained piece will be used for the heavy transverse brace on the top.

This billet is larger and offers more possibilities.
I cut the sealer off the end to expose the end grain. And split the billet in the center to establish a split face that follows the grain.
I now have a reference face on each piece. We can see that the grain is not straight.  This piece is bowed.
Looking under the straightedge in this picture we can see just how much. In a perfect world I'd look for another piece of brace wood that is straighter. In the real world perfectly straight grain is hard to find so I use a plane to cut some of the bow out and make this face straighter. 
I go ahead and split this piece again. And again.
And touch up each split face to give me a straight reference face on each piece. Some folks  begin sawing braces at this point but following William Cumpiano's advice I split the braces again to create a second split face perpendicular to the first.
I'm now splitting the piece at a right angle to the first split face and again the split follows the grain. See how the grain runs through this piece at an angle? And the split face isn't perfectly straight
The plane helps me to "average" the difference. Occasionally you find unhappy surprises like this little knot. You just have to work around them.
This method usually produces  more waste than usable stock but you are assured of the strongest possible braces from whatever wood you are using. These pieces have two split faces. This piece has two split faces and it is easy to see the twist in one plane and a bow in the other. You can only get short braces out of this piece of wood.
Saw To Shape
Selecting the  straightest piece I begin sawing the arms of the x-brace. I cut the pieces a bit oversized so that I can sand or plane them to the proper thickness before use.
Here is what's left of the billet. Most of the wood on the left is scrap. These braces are pretty well quartered and have reasonably straight grain.
Radius the Braces
The bottom of the braces must be curved to match the radius of the top or back. Here I'm using templates to mark my braces.
Several swipes with a plane get me close to the pencil line. And I finish up with a quick trip to the appropriate hollow form with sandpaper.
Make the X-Brace
Flip one brace upside down and clamp them together in a vice. Use a protractor to draw two lines. Using a small saw cut very carefully inside the lines and exactly half way thru the brace.
Look at the curve of the braces, you're cutting the top of one brace and the bottom of the other. Pop out the pieces with a 6mm chisel.
You should get a neat  clean slot. Flip one brace over, and . . .
clean up the slot with a file until the pieces fit snugly. The x-brace matches the blueprint! (It's been a good day!)
The x-brace fits together tightly enough that it won't come apart even if shaken. Here all the braces are laid out on the top before gluing.

Back to Assembly Steps                             Home                    On to "Preparing the Neck"