Stropping compound must be applied to a surface in order to be used. Many surfaces can be used with compounds, leather strops being one of the most common. The compound is applied to the surface and then the edge is passed over it.
Note that honing compound is the final abrasive used in the sharpening process. The abrasive particles are extremely small and will polish an existing edge to a mirror finish, but are not aggressive enough to bring a dull edge back to sharp. The edge being sharpened must have been taken through the finest sharpening stones before the compound is used for it to be effective.