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