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