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