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