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