Get one of those pool noodles but don't use it to outline the edges. Instead, put one on each vertical edge so it extends on down beyond the lower edge of the slide. The idea is to make it long enough that it will be in your field of vision when you walk around the corner.
Then, if you still have a tendency to come charging around the corner, put a traffic cone on the ground right beneath it. The cone will be handy to have if you are ever broke down and it will help you avoid the "El Cabong" at the front corner.
Don't ask me why I have such a well thought out solution to this problem.
