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