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