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