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