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