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