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