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