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