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