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