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