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