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