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