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)(11,15)(12,13)(14,16)(17,18,21,24)(19,22,20,23)(25,26,30,31)(27,28,35,32)(29,33,37,39)(34,36,38,40)(1,3)(2,7)(4,5)(6,8)(10,13)(11,16)(17,19,21,20)(18,22,24,23)(26,31)(28,32)(29,37)(34,38)(2,4)(3,8)(9,11,12,16)(10,14,13,15)(17,19,21,20)(18,22,24,23)(25,27)(26,32)(28,31)(29,38)(30,35)(33,36)(34,37)(39,40)(1,4,6,2)(3,5,8,7)(9,10)(11,14)(12,13)(15,16)(17,18)(19,22)(20,23)(21,24)(25,28,30,32)(26,27,31,35)(29,36,37,40)(33,34,39,38)(1,5)(2,3)(4,8)(6,7)(9,11)(10,14)(12,16)(13,15)(17,20,21,19)(18,23,24,22)(25,29)(26,33)(27,34)(28,36)(30,37)(31,39)(32,40)(35,38)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.