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