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