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