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