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