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