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