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