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