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