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