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