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)(12,20)(13,14)(16,22)(17,19)(18,24)(21,23)(25,26,31,28)(27,32,34,30)(29,33,39,36)(35,40,37,38)(1,2,4,6)(3,5,7,8)(9,10)(11,17)(12,20)(13,14)(15,19)(16,22)(18,23)(21,24)(25,27,31,34)(26,32,28,30)(29,37,39,35)(33,38,36,40)(3,7)(5,8)(10,14)(15,17)(16,20)(23,24)(27,34)(30,32)(35,37)(38,40) involution — undirected(1,2,4,6)(3,5,7,8)(9,11)(10,15)(12,21)(13,19)(14,17)(16,24)(18,22)(20,23)(25,28,31,26)(27,30,34,32)(29,33,39,36)(35,40,37,38)(1,2)(3,5)(4,6)(7,8)(9,12)(10,16)(11,18)(13,22)(14,20)(15,23)(17,24)(19,21)(25,29)(26,33)(27,35)(28,36)(30,38)(31,39)(32,40)(34,37) involution — undirected(1,3,4,7)(2,5,6,8)(9,10)(11,15)(12,16)(13,14)(17,19)(18,23)(20,22)(21,24)(25,30)(26,27)(28,34)(29,38)(31,32)(33,35)(36,37)(39,40)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.