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