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