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)(11,16)(12,20)(13,17)(14,15)(18,24)(19,22)(21,23)(25,26,29,32)(27,30,34,39)(28,35,37,31)(33,40,36,38)(2,5)(3,8)(10,15)(16,22)(17,20)(23,24)(25,27)(26,30)(28,36)(29,34)(31,40)(32,39)(33,37)(35,38) involution — undirected(2,5)(6,7)(9,11,14,19)(10,16,15,22)(12,21,13,18)(17,24,20,23)(25,28,29,37)(26,31,32,35)(27,33,34,36)(30,38,39,40)(1,3,4,8)(2,6,5,7)(9,12,14,13)(10,17,15,20)(11,18,19,21)(16,23,22,24)(27,34)(30,39)(33,36)(38,40)(10,15)(16,22)(17,20)(23,24) involution — undirected(9,13,14,12)(10,17,15,20)(11,18,19,21)(16,24,22,23)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.