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