What I did was to get two 30" x 48" poster boards from Staples. I spray painted them black, and added a layer of Moss Green paint. I then drew up a hex grid using AutoCad, and plotted it out on large sheets of paper using the plotter at my office. I actually made the number of hexes larger than what is required for a Commands and Colors game in order to also be able to play Battles of Westeros on this table. The hexes were originally sized at 4" across the flats of the hexes, but since this didn't quite fit on the poster boards, I scaled them down slightly so that they are really 3 7/8" across. Then I aligned the plots on the boards and stuck a tack through at each point of intersection. The small holes were connected with pencil lines that were then draw over with a green Sharpie. The Commands and Colors edge border and section dividers were then drawn on with a black sharpie. Here are a couple of photos of the finished board:
Here are also some photos of how I plan to arrange units for gameplay. The first is an eight stand barbarian warrior unit. Since in the game, this is a four block unit, two bases will be removed each time the unit takes a hit.
Being based on 40mm x 15mm bases as per heavy foot, this is an easy fit. I've also tried doing the same with an eight stand unit of barbarians based on 40mm x 20mm bases for use as medium infantry.
This seems a little tight, and I might instead just use four bases per unit as shown below:
Here is a three stand unit of Gallic medium cavalry:
And one of Numidian skirmishers:
Finally, a unit of Roman heavy infantry:
Seems to me, this is the way Commands and Colors Ancients is meant to be played.
Now, I have to work out how to put together a larger board for Epic-sized games.