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