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)(13,14,19,22)(15,20,24,17)(16,25,18,21)(23,27,28,26)(5,7,8,12)(6,9,10,11)(15,23)(16,18)(17,26)(20,27)(21,25)(24,28)(1,2,3,4)(13,15)(14,20)(16,23)(17,22)(18,28)(19,24)(21,26)(25,27)(6,10)(9,11)(13,16,19,18)(14,21,22,25)(15,23,24,28)(17,27,20,26)(7,12)(9,11)(13,17,19,20)(14,15,22,24)(16,26,18,27)(21,28,25,23)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.