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