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