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