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