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