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