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)(11,16)(12,18)(13,19)(14,20)(15,17)(21,24)(22,23)(26,32)(27,28)(30,40)(34,37)(9,11)(10,16)(12,13)(14,17)(15,20)(18,19)(21,22)(23,24)(25,26,31,32)(27,33,28,36)(29,30,39,40)(34,38,37,35)(1,2)(3,5)(4,6)(7,8)(10,17)(11,20)(13,21)(18,23)(25,27,31,28)(26,33,32,36)(29,37,39,34)(30,35,40,38)(3,7)(5,8)(9,12)(10,18)(11,21)(13,20)(14,19)(15,22)(16,24)(17,23)(25,28,31,27)(26,33,32,36)(29,37,39,34)(30,38,40,35)(1,3,4,7)(2,5,6,8)(9,13,15,21)(10,19,17,24)(11,12,20,22)(14,23,16,18)(25,29)(26,30)(27,34)(28,37)(31,39)(32,40)(33,38)(35,36)(1,2)(3,5)(4,6)(7,8)(9,14)(10,11)(12,19)(13,23)(15,16)(17,20)(18,21)(22,24)(25,30)(26,29)(27,35)(28,38)(31,40)(32,39)(33,37)(34,36) 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.