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