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