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