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