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