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) involution — undirected(2,3)(6,9)(10,11)(15,21)(16,23)(18,24)(20,26)(22,27)(25,28) involution — undirected(1,2,4,3)(13,14,17,19)(15,18,22,25)(16,20,23,26)(21,24,27,28)(1,3,4,2)(13,15,16,21,17,22,23,27)(14,18,20,24,19,25,26,28)(5,7,8,12)(6,10,9,11)(14,19)(18,25)(20,26)(24,28)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.