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