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