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