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