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