Treat your edges like a fine knife. Once the edge angle is defined you should be able to maintain the sharpness by honing and polishing (maintenance).
I have my boards ground, which should establish a flat base and set your edge angles; for me, it's 0.5 degrees on the base and 2 degrees on the edges. Next, the boards are hot-boxed at the same shop.
From there I will use the Wax Wizzard on the base and POLISH the edges. I do not tinker with the base metal. For the sides, I use a 2 degree guide and spring clamp to hold the files and employ a series of 4 diamond files of ascending courseness followed lastly with an Arkansas whetstone.
http://www.tognar.com/deburr_tips_edge_polish_repais_ski_snowboard.html