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