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