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