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)(14,18)(15,19)(20,23)(21,27)(22,26)(24,28)(2,3)(5,6)(7,11)(8,10)(9,12)(13,14,17,18)(15,19,22,26)(16,23,25,20)(21,28,24,27)(5,7,8,12)(6,9,10,11)(13,15,17,22)(14,19,18,26)(16,24,25,21)(20,28,23,27)(1,3,4,2)(7,12)(9,11)(13,16)(14,20)(15,21)(17,25)(18,23)(19,27)(22,24)(26,28)(6,10)(9,11)(16,25)(20,23)(21,24)(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.