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