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