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