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