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