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