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