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