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