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