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