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