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