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