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