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