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