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