Hold the blade bevel against the surface of the strop with light pressure and move the blade away from the cutting edge.
Stropping compound is an extremely fine abrasive used in the final polishing stages of sharpening.
Stropping compound must be applied to a surface in order to be used.
A strop is a substrate that is used after the finest stone for the final stage of the sharpening process.
Leather strops come in both suede and smooth options. Some even have both on the same strop.
A strop can be used without any compound. Sharpeners of straight razors for instance often prefer using a smooth leather strop with no compound applied.