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