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