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