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