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