Don't think of it like a circle if that's what's giving the issue. It's only a circle in that the last one will trump the first one (i.e. the only element water beats is fire).
Fire beats Earth and Air.
Earth beats Air and Water.
Air beats Water.
Water beats Fire.
I think, at least. The concept of a circle is not really efficient for explaining this because a circle, by definition has no beginning and no end. So if you represent it as a circle, then every element can beat every other element in the list. (i.e. if you start at water in a "circle", then it would be greater than the other 3 and the same would be true for every other element if you started your circle at that point.)