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