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