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