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