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