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