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