How did you go about painting the grey and getting the white on the outer sole? Did you just use fabric paint or what?
Acrylics and then sealed it with clear enamel spray. It's gonna flake I'm sure but it looks nice. I'm actually fairly certain the prop makers actually did what I've done, the close up of the shoes show the coloring isn't perfect. And they did paint the soles and sides of his Asics after all when shoes in the color they wanted were available for another style.
*If anyone wants a pair of their shoes modified I don't mind doing it for commission, it's not difficult but it does require a lot of work.