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