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