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