Just a guess: One of the strops, the less-smooth one, would be used first then you would finish on the smoother one. Perhaps the rougher one would only be needed occasionally. This would be the same as the instructions given for the Hand American 830 strop -- it's rougher side is purposely "roughened up" with a fine pattern embossed into it. Your strops don't look to have as radical a difference between the two but the principle could be the same.
As JimmyHAD recommends, I would also get a fabric strop of some kind. See the following: http://straightrazorpalace.com/strop...strop-man.html. That has a recommendation from a well-respected strop maker:... when stropping you want to use the linen first to remove the oil off of the blade edge. Follow that by the outer side slightly textured non-cordovan horsehide. And to finally finish with the cordovan.