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