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