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)(15,20)(16,26)(17,21)(18,25)(19,23)(22,27)(24,28) involution — undirected(1,2)(3,4)(6,9)(10,12)(13,15,19,25)(14,20,23,18)(16,21,27,24)(17,22,28,26)(5,7,8,11)(6,10,9,12)(13,16)(14,21)(15,22)(17,20)(18,28)(19,27)(23,24)(25,26)(2,4)(13,17,19,28)(14,22,23,26)(15,24,25,21)(16,20,27,18)(6,9)(10,12)(16,27)(17,28)(21,24)(22,26) 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.