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