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