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