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