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