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