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