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)(25,26,29,33)(27,30,35,31)(28,32,37,40)(34,38,36,39)(1,2)(3,6)(4,7)(5,8)(10,15)(12,16)(18,21)(20,23)(25,27)(26,30)(28,36)(29,35)(31,33)(32,39)(34,37)(38,40) involution — undirected(1,3)(2,5)(4,8)(6,7)(10,15)(11,17)(13,22)(20,23)(25,27,29,35)(26,31,33,30)(28,34,37,36)(32,39,40,38)(3,8)(5,6)(9,11)(10,16)(12,15)(13,19)(14,17)(18,23)(20,21)(22,24)(25,27)(26,30)(28,36)(29,35)(31,33)(32,39)(34,37)(38,40) involution — undirected(1,3)(2,6)(4,8)(5,7)(9,12,14,16)(10,17,15,11)(13,20,22,23)(18,24,21,19)(25,28)(26,32)(27,34)(29,37)(30,38)(31,39)(33,40)(35,36)(1,2)(3,6)(4,7)(5,8)(9,13)(10,18)(11,19)(12,20)(14,22)(15,21)(16,23)(17,24)(25,26)(27,30)(28,32)(29,33)(31,35)(34,38)(36,39)(37,40) 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.