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