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