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