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