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