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