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