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