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