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