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