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