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