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