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