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