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