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