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