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