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