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