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)(15,19,20,17)(21,22,26,25)(23,28,27,24)(6,9)(10,11)(13,14,16,18)(15,17,20,19)(22,25)(24,28)(1,3,4,2)(13,14)(15,17)(16,18)(19,20)(21,23)(22,24)(25,28)(26,27)(5,7)(6,10)(8,12)(9,11)(13,14)(15,17)(16,18)(19,20)(21,24,26,28)(22,27,25,23)(5,6)(7,10)(8,9)(11,12)(13,15,16,20)(14,17,18,19)(21,25,26,22)(23,28,27,24)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.