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