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