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