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