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