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)(13,14,19,22)(15,23,26,27)(16,17,21,18)(20,24,28,25)(5,6)(7,11)(8,10)(9,12)(13,15,19,26)(14,20,22,28)(16,27,21,23)(17,24,18,25)(2,4)(6,10)(7,8)(11,12)(13,16,17,22,19,21,18,14)(15,20,25,23,26,28,24,27)(5,7,9,8)(6,11,12,10)(13,17,19,18)(14,16,22,21)(15,24,26,25)(20,27,28,23)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.