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