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