All you need for these are a old pair of shoes, tape, and spray paint.
They aren't perfect, but they'll work.
Before (I don't have a picture, ah!), but the bottom was a metallic brownish color. I had them in the goodwill bag, but thought I may be able to do something with them.
First, you cover EVERYTHING you don't want paint on. I used electrical tape and scrap fabric. A plastic bag on the inside shields that pretty well.
Since the bottoms were dark, I used white paint first, then the neon.
Let dry, peel, and wear!