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