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