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