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