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