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