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