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