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