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