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