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