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