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