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)(13,14,17,16)(15,18,19,20)(22,23)(24,28)(5,6,8,10)(7,9,11,12)(15,19)(18,20)(21,22,25,23)(24,26,28,27)(7,11)(9,12)(13,15)(14,18)(16,20)(17,19)(21,23,25,22)(24,26,28,27)(1,2)(3,4)(5,6)(7,9)(8,10)(11,12) involution — undirected(5,7)(6,9)(8,11)(10,12)(13,16,17,14)(15,20,19,18)(21,24)(22,26)(23,27)(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.