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