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