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