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