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