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