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