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