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