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