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