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