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