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