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