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)(11,15,19,17)(12,20,21,16)(18,23,24,22)(25,26)(27,31)(28,33)(29,34)(30,32)(35,38)(36,39)(37,40)(2,5)(6,7)(9,10)(11,17)(12,16)(13,14)(15,19)(18,23)(20,21)(22,24)(25,27,30,34)(26,31,32,29)(28,36,37,35)(33,39,40,38)(2,5)(6,7)(10,14)(15,17)(16,20)(22,23)(26,32)(27,34)(28,37)(38,39) involution — undirected(1,2)(3,6)(4,5)(7,8)(9,10)(11,15)(12,16)(13,14)(17,19)(18,22)(20,21)(23,24)(25,27)(26,29)(28,35)(30,34)(31,32)(33,39)(36,37)(38,40) involution — undirected(1,2)(3,7)(4,5)(6,8)(9,11,13,19)(10,15,14,17)(12,18,21,24)(16,22,20,23)(25,28,30,37)(26,33,32,40)(27,35,34,36)(29,39,31,38)(1,3,4,8)(2,6,5,7)(9,12,13,21)(10,16,14,20)(11,18,19,24)(15,22,17,23)(25,29)(26,27)(28,38)(30,31)(32,34)(33,36)(35,40)(37,39)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.