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