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