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