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