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