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