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