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