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