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