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