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