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)(13,14,18,21)(15,22,19,16)(17,20,27,28)(23,26,25,24)(6,9)(7,11)(13,15,18,19)(14,16,21,22)(17,25,27,23)(20,26,28,24)(13,16,19,14,18,22,15,21)(17,26,25,28,27,24,23,20)(5,7,8,11)(6,10,9,12)(13,17,18,27)(14,20,21,28)(15,23,19,25)(16,24,22,26)(1,3,4,2)(6,9)(10,12)(13,15,18,19)(14,16,21,22)(17,25,27,23)(20,26,28,24)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.