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