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