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