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