A wonderful and inexpensive tool. Its cost will be 15-20 hryvnia (40-60 rubles).
You just need to glue sandpaper to the sole of the shoe. The shoes need to be degreased, greased with glue and attach sandpaper cut along the contour to it. Check that everything is glued. We leave the shoes for a day, for a greater effect, weights can be put inside. It is important to remember that sandpaper is on a fabric basis and 3-4 mm thick. It should also be understood that it will be erased and during the winter it will need to be changed.