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