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