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