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