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