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