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