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