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