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