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