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