Though the styrofoam works good for many, I have leg injuries and metal knees that make it very painful to work on my knees at floor level. I also hate breaking up sheet stock on saw horses, because pieces fall to the floor, especially when cross cutting.
So I built a "Cutting Table". A frame of 1 X 4" of about 30 X 70" with 2 X 4 cross pieces laid flat and flush with the top of the 1 X 4 frame where needed to allow attaching Banquet Table Legs bought from Northern or Harbor Freight, plus one additional across the center. The entire frame is held together with biscuits and glue, so the only metal in the frame is the short screws that attach the legs. Over 1" of the depth of the top of the table has no metal in it at all. The legs fold up inside the recess below the 2 X 4's and inside the 1 X 4 frame and I store this table inside my shop, on it's edge and against my sheet stock where it consumes less than 4" of space. I can cut a panel in any direction with my circular saw blade set for the material thickness plus 1/8 - 1/4" with no fear of damage to the blade. The kerfs in the table caused by this are never a problem, and if they should ever become objectionable or weaken the frame I'll just remove the legs, make a new table top and add the legs to it. I can make cuts in any direction with the stock roughly centered on the table. There is no breakage as I complete the cuts, and both the stock and off-cut remain on the table at the end of the cut. I can then remove the off-cut and re-center the stock on the table for the next cut.
I use straight edge clamps and a circular saw for breaking down sheet stock outside my shop and then final cut the pieces on my Unisaw in the shop. The shop is too small for managing full sheets, so this works best for me. I have added a piece of Lexan to the shoe of my circular saw with a hole to allow the swing guard for blade protection and the front of this hole is cut to perform a zero clearance function where the blade teeth rise up through the workpiece. There are also channels in this piece to match the shape of the extrusion on my straight edge clamps, so the saw stays on track for perfectly straight cuts. Since I built this before track saws became available, and it works so well for me, I have seen no reason to replace it with an expensive track saw.
My straight edge clamps were purchased from Peachtree Supply www.ptreeusa.com
in case anyone is interested. This sheet break-down method has been working well for me for about 15 years.