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