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