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