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