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