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