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