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