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