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