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