Mate
Any wedge shaped piece of wood that fits into crevice between the upper-leather and the sole will do the job.....
This is a link to the one I used http://mypolishstash.blogspot.com/2013/01/new-blog-series-how-i-do-it-cuticles.html
My wife corrected me, it is not a nail cleaner, but a cuticle remover....;-)...
Not to steal Pauls thunder, but I would just( actually have used), use black paint semi flat, and paint the whole of the sole.....