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