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