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)(13,14,19,15)(16,21,24,23)(17,26,27,28)(18,25,20,22)(2,3)(5,6)(7,10)(8,9)(11,12)(13,15,18,25,19,14,20,22)(16,23,26,27,24,21,28,17)(1,2,4,3)(6,9)(10,11)(13,16)(14,21)(15,23)(17,22)(18,26)(19,24)(20,28)(25,27)(1,3,4,2)(5,7,8,12)(6,10,9,11)(16,24)(17,27)(21,23)(26,28)(13,17,20,21,19,27,18,23)(14,16,25,28,15,24,22,26)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.