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