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