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