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