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