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