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