Foot impression generating apparatus comprising impression platforms including buns of open-cell sponge material bonded to an supporting non-porous skins formed of non-blown sponge material is utilized for making foot impressions by a consumer. The sponge material comprises a blended mixture of elastomeric thermosetting material and low melting temperature thermoplastic material chosen such that the buns and skins are respectively flexible and then become rigid when heated and then cooled above and below the plastic temperature range of the thermoplastic material. The consumer steps into heated impression platforms to form the foot impressions and then they are cooled and "frozen" in place. Next, scanning means are used to create a digital contour map of the foot impressions. Then a digitally controlled milling machine is utilized for forming shoe inserts in conformance with the digital contour map.