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