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