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