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)(11,17)(12,15)(13,18)(14,16)(19,24)(20,22)(21,23)(25,26,30,31)(27,34,32,28)(29,33,38,39)(35,37,40,36)(1,3,5,8)(2,6,4,7)(9,11,14,12)(10,15,16,17)(13,19,21,20)(18,22,23,24)(25,26,30,31)(27,28,32,34)(29,33,38,39)(35,36,40,37)(1,2,5,4)(3,6,8,7)(10,16)(15,17)(18,23)(22,24)(26,31)(27,32)(33,39)(35,40)(1,2,5,4)(3,6,8,7)(9,10)(11,15)(12,17)(13,18)(14,16)(19,22)(20,24)(21,23)(25,27,30,32)(26,28,31,34)(29,35,38,40)(33,36,39,37)(1,4,5,2)(3,7,8,6)(9,12,14,11)(10,17,16,15)(13,20,21,19)(18,24,23,22)(25,28)(26,32)(27,31)(29,37)(30,34)(33,35)(36,38)(39,40)(9,13,14,21)(10,18,16,23)(11,19,12,20)(15,22,17,24)(25,29,30,38)(26,33,31,39)(27,35,32,40)(28,36,34,37)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.