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