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