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