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