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