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