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