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