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