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