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