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