One vertex per element, one color per generator, with an edge from x to x·s.
(1,2,4,5)(3,7,8,6)(9,10,15,18)(11,16,20,24)(12,14,17,13)(19,21,22,23)(25,26,29,32)(27,30,34,38)(28,31,36,39)(33,40,35,37)(2,5)(6,7)(9,11)(10,16)(12,21)(13,19)(14,22)(15,20)(17,23)(18,24)(25,27)(26,30)(28,35)(29,34)(31,37)(32,38)(33,36)(39,40) involution — undirected(9,12,13,10,15,17,14,18)(11,16,19,23,20,24,22,21)(25,28)(26,31)(27,33,34,35)(29,36)(30,37,38,40)(32,39)(1,3,4,8)(2,6,5,7)(9,13,15,14)(10,12,18,17)(11,19,20,22)(16,21,24,23)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.