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