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