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