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