One vertex per element, one color per generator, with an edge from x to x·s.
(5,6,9,11,8,10,7,12)(13,14)(15,19)(16,18)(17,21)(20,24)(22,25)(23,27)(26,28)(1,2)(3,4)(6,10)(11,12)(14,18)(16,24)(19,25)(20,21)(22,28)(26,27) involution — undirected(2,4)(5,6)(7,11)(8,10)(9,12)(13,15,17,23)(14,19,21,27)(16,22,24,28)(18,25,20,26)(5,7,8,9)(6,11,10,12)(14,18)(16,24)(19,25)(20,21)(22,28)(26,27)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.