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