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