One vertex per element, one color per generator, with an edge from x to x·s.
(5,6)(7,12)(8,10)(9,11)(13,14)(15,24)(16,21)(17,22)(18,27)(19,23)(20,25)(26,28) involution — undirected(1,2)(3,4)(13,15,18,25,19,26,16,22)(14,20,21,24,23,17,27,28)(2,4)(5,7,9,8)(6,10,11,12)(13,16,19,18)(14,21,23,27)(15,25,26,22)(17,24,20,28)(2,4)(5,8,9,7)(6,10,11,12)(13,17)(14,22)(15,21)(16,24)(18,28)(19,20)(23,25)(26,27)(15,26)(17,20)(22,25)(24,28) involution — undirectedA 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.