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