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