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