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