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