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