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