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