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