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