This video shows the carving and ganaching of a sports shoe out of a rectangular cake. I cut out two shoes, but in the end, only had time to decorate one. All the decorations are done in fondant. I had a real Converse to look at in order to get some of the detailing correct.
To make the first rough cuts, i use a serrated knife, like a steak knife. For the finer detailing i use paring knives.
With this same tutorial you can make a cowboy boot or a lady's boot.
The recipe used is here