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