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