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