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