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