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