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