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