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